Nice vise, looks to be in great shape.
If you don't mind weighing it, that will narrow down the date. If it's about 110 lbs, the spec for the 107 in the catalog page Tom posted above, then its likely from about 1967 on - that's the first year I have evidence of a vise made with Ductalloy. It will also have a maximum opening of 9", measured with the end of slide even with the back of the static jaw.
If it's around 210 lbs, and the max opening is 12" (per the 1950 catalog page below, when Rae was still made in Hamilton), then it's not Ductalloy, and would be from about 1965 to 1967 or so. 1965 is the last year I've found a directory listing Rae vises being made by McCoy Foundry, and the first year for an OTACO listing with Rae vises. Since directory listings aren't always updated, and OTACO may have introduced Ductalloy versions of some models before others, these dates aren't exact.
If you do measure and weigh it, please post the results - they'd be helpful!
