For those not particularly interested in expending copious quantities of cash in order to purchase an early Huret Success / Duopar front derailleur (...or a later one for that matter with that clever Spring Push Plate) only to potentially destroy any supposed "collectible" value by putting it to good use, I offer the following economy suggestions begot of personal experience (...although, I would think the matter of whether or not they are suitably paired with a Jubilee rear derailleur will depend upon one's individual perspective):
1) An early 1980's SunTour Le Tech model FD-3200 would be my first choice here. It is a very classy looking bottom pull parallelogram mechanism having an alloy body, clamp, and link pivot arms with chrome plated steel chain guide. It tips the scales at a respectably light 104 grams while having proved itself to be very durable and precise from my own experience. Best of all, it has a whopping 26 tooth maximum front chain ring differential with a minimum difference requirement of only 6 teeth (...and you can "cheat" those numbers a bit depending upon the particular details of a given bike setup), all of which makes it a perfect candidate for those really wide spaced triple ring setups. The only downside to this unit is that they are not necessarily the easiest component to find, although they can usually be had NOS for under fifteen dollars when you do (...yes, even on eBay).
2) Despite the fact that its counterpart rear derailleur was fraught with design problems that were sure to manifest themselves over time (...most especially in an "off road" environment), the 1980's SunTour Mountech model FD-2700 is a very reliable unit having virtually the same specifications as the aforementioned Le Tech. The good news here is that these are somewhat easier to source because they were made in larger quantities than the Le Tech model. The bad news is that pricing can be quite volatile according to my own observations. My conjecture in this regard is that the Mountech rear derailleur's tarnished reputation tends to moderate pricing of the FD in certain circles while those who seek to sustain their own vintage Mountech equipped bikes covet them enough to make things occasionally quite interesting in a competitive venue such as eBay.
3) And for the truly bargain minded, you might consider the Shimano Alivio model FD-MC17 circa 2000 (...yes, out of the CR List timeline by a long shot but passably vintage looking, and besides, we are specifically talking about components which may be employed to affect a peculiarly vintage task here after all). This is a hinged type, top swing, bottom pull front derailleur having an alloy body and clamp mechanism, stainless steel pivot link arms, and chrome plated steel chain guide. It has a maximum 20t front chain ring difference, which should prove worthy for all but the most extreme applications. I am currently using one of these very derailleurs on my SlopCycle bike in conjunction with a 46/42/26 compact half-step plus granny triple and have found it to perform well beyond any expectations I would normally have associated with a component that I purchased off the shelf at my LBS for less than ten dollars (...and that would be including sales tax).
Yes, I am quite sure that there are other suitable front derailleurs (...and if I were at home right now, I could probably "look up" a few of them myself). But these three are ones that I am very familiar with and would recommend to others without hesitation.
There is one last, rather obvious, comment I feel that I should make with respect to any contemplated half-step plus granny setup. As the "suicide shift" from the middle ring down onto the smallest one increases in size, so does the likelihood of unintended chain derailment under certain conditions. To that end, I would strongly suggest that you consider employing some form of chain minder (...an N-Gear Jump Stop being my own preference, but there are several other manufacturers out there who also make a quality product) so as to virtually eliminate this potential problem. But, everyone out there knew that already....
Robert "doin' the half-step off to sleep now" Broderick ...the "Frozen Flatlands" of South Dakota Sioux Falls, USA
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>From: "Cheung, Doland" <CheungD@bv.com>
>To: <classicrendezvous@bikelist.org>
>Subject: [CR]FD that accommodates triple/half-step??
>Date: Wed, 7 Feb 2007 17:15:57 -0600
>
>Well, since we are on the subject, other than the Huret Success FD, are
>there any other candidates that would work on a triple and half-step
>set-up that would combo nicely with a Huret Jubilee RD? I have a
>Jubilee long cage RD and some Sugino AT triple cranks and need an FD for
>them. Any candidates?
>
>Doland Cheung
>SoCal