It's all so confusing!!!!!

Well it's not really but I thought I should throw my questions out to the collective knowledge of the local AK builders and see what comes up.
Better brains then mine!
I have just picked up a couple Romy G parts kits. I'll be needing a couple of receivers to put these together.
The question's are:

What receivers? Flat, bent 80% or complete?
Screws or rivets.

I have none of the specific tools to build AK's but I do have a Bridgeport mill (I'm a machinist) A lathe, access to a press, lotsa drills and taps etc. I have a Tig welder at work.

Keep in mind that I will be likely be building only these two kits (unless of course the builder bug hits me hard)

Thanks in advance for the feedback.