Regarding Peter Brown's Benelux Tourist derailleur on eBay #390147658135
that's the first Tourist version with its cranked/angled derailleur body. It was introduced at the 1953 Cycle Show and it's a 1954 introduction, and called "Benelux Tourist."
Catalogue spec says that first Tourist version has a max cog capacity of 26t when used with its derailleur hanger, or 28t when used with a Cyclo-style clip-on chainstay mount. I would suppose that the more forward location for the derailleur using the clip-on chainstay mount would allow it to clear the larger 28t cog when shifting upwards. Some time ago, I tried it with its derailleur hanger, and couldn't manage higher than 26t, just like the catalogue spec.
The second-version Mark 8 Tourist came out in 1958, has a straight-derailleur body, which puts the pulleys farther down, allowing a 28t freewheel cog size according to catalogue spec.
This first Tourist version is a very rare bird on eBay in my observations; the later Tourist Mark 8 is much more frequently seen. Judging from the photos, Peter Brown refurbished this derailleur very well.
Sources: 1955 Cycle catalogue and the Boneshaker article by Gordon Selby in Autumn 2004.
Peter Brueggeman
La Jolla California USA
4peebee(at)peterbrueggeman.com