Once the only option, now more - SGM Tactical Vepr Rifle Receiver Insert

This adapter used to be the only option if you get one of the slanted receiver VEPRs.
I wanted to make a wood-looking VEPR conversion, so I bought this thing. The adapter itself seems to be sturdily made out of steel. However, it's actually narrower than the standard stamp receiver so you have to modify the stock to get it to work for you.
CNC Warrior made some triangular stocks now with slanted back. So you can get a folding metal stock from them. I'd say that it's probably a better choice. But if you are like me, you want wood furniture, this would be the only choice. And it performs well so far after a couple of hundreds of rounds.