Not much honestly. Ammo has been a lot more available, I have a pile of it, and if the rifle has already been butchered it wouldn't be destroying anything real nice. No way I would do this to anything that has a hope of restoration, and there are plenty of roughly treated Enfields out there,
Do a little research into the 7.62x54r conversions. I wish I could find a cheap beater Enfield that bubba had already tainted to give it a go. Unfortunately, even the clap trap ones are going for more than I want to put into such a risky project.
http://www.theoutdoorstrader.com/threads/822960-FS-Mosin-Nagant-91-30-Parts?highlight=mosin
Not mine, but should get you well on your way to having it up and running. Bolt parts are pretty cheap if you look around Numrich, Centerfire Systems, CDNN, and some of the others.