Maybe loctite will make it right... - B-Square Mosin-Nagant "Scout" Mounts (Long Eye Relief) - Polish 44, Russian 44, Chinese 53, Blue 18522

As mentioned in other posts, make sure you can disassemble the iron sights on your Mosin Nagant before buying. If you can, the install is fairly easy. They even include some allen wrenches and scope rings, which is a nice touch given the price point. Unfortunately, the mount shook loose after a few dozen rounds, so we plan to try blue loctite-ing it before we go out next. Any scope mounted on a standard Mosin Nagant will need very long eye relief, and we found the NcSTAR Pistolero Rifle Scope - 2.5x30 available on this site made a good match.
Pros: Good price; comes with rings.
Cons: Shook loose in a hurry

This review was written in the old system and had content requirements that are different than reviews written today.