While taking pics of my Mondia Special set up for cyclocross to show Mondia did it for the benefit of a CR member, I noticed that I had an Oro freewheel in use. Following that observation, I rustled through my box of Oro gears and indeed the worn ones that I used while escaping grad school were sitting at the bottom like shards in some ruin. They were used on my trusty Mondia all right and that was in 1970, so we're edging closer to the '60's. For the benefit of Bob Hovey, whose questions regarding restoring a '60's Cinelli initiated this discussion of proper Regina freewheels, I do have a G.S. Corse core, but only two gears are still here. It all works fine. If you need it, cover shipping and I'll send. It seems pretty convincing that Phelps' estimate of the beginning of the '70's for widespread Oro installation is a good one, such that something like this Corse is a good bet for period accuracy. Can't find them now that I need them, but those old Bicycling mags in the late '60's and early '70's featured a centerfold...a bike, like the Hetchins I ogled for years...and a menu of parts. Perhaps a CR archive of such mags is in order. Burnt out librarians such as I regard that practice as a little bit of heaven.