617, 22 - no thanks. Ruger is making an SP101 that will fill that market much cheaper.
625, 45 ACP, interesting, but I think the 44 mag would sell better. perhaps this could be the 3rd gun done for us.
610. Couldn't find it, only the 10, but I believe this to be a 38, so not thanks, there are a few filling this market.
The 500 no, but the 460 in a 4.2" barrel would be of interest since it could use the 45 Colt, 454 Casull and 460 ammo.
But.... The 629 would be the best seller, but I think the 460 wound be the next best due to versatility and it would look really cool with the big frame and small barrel, it would optically look like a snubby.