I scoped mine several years ago, for ammo testing, but it wasn't much fun to shoot. I just bought a $7 weaver base, a 4X Simmons pistol scope, and a set of low rings. About $125 all told, but if I was going to do it again I'd put a 2X on it, it's a lot easier to see with than a 4X, too much magnification and obvious wobbling. It shot well, but only from a solid benchrest. The mount base uses the same two holes as the rear sight base, but once it's scoped, there's no holstering it, you either carry it or lay it down. Holsters for un-scoped BuckMarks are easy to find, just match the proper barrel length to it. And if you buy a leather holster, don't leave the gun in it, it WILL rust it.
Hope this helps.
Papajohn