I believe they are all 7* included angle. I got mine from snap on, p/n r-121. It sure looked like a pos compared with other reamers I have used, which are usually sharp enough to slice you wide open if handled carlessly. I think the trick to the snap-on reamer is low rpms with mucho pressure. I did it likr that on my lathe and it worked out just fine.
As far as all makes and models sharing the 7* taper, I don't know.