by ronin
G,
I can't vouch for the method which Doc Rob mentioned about rivet removal. But, that is simply because I haven't tried it yet.
The one that I know of involves dremeling out the rivets on the elbows and shoulders using a bit head designed for metal cutting. Once the rivet tops are dremeled off, you can remove the body of the rivet itself.
This make it easier when splitting the upper arms to attempt casting. Also, you can more easily access the inner torso\shoulder socket connector and cast that too.
Once that is done, you have a few options. You can purchase metal rivets from a site like microfasteners.com. They might be slightly larger than the existing Joe rivets but you can mod them to fit and then crimp.
Or you can cast plastic rivets and crimp them. Casting plastic ones is obviously much more cost effective because you can use the leftover product material from your main figure part casting and it doesn't have to be a lot.
The above was detailed to me by Alyosha awhile ago. Have tried it a couple of times so far and I am sold.
There is a third option about rivets which I have also begun to explore on my own. I am trying to get in touch with a local jewelry maker who happens to be retiring. I am trying to see if he can teach me how to perform small part metal casting for the arm rivets and crotch t-hooks.
Once I get that down pact, I think that I can pretty much produce my own ARAH style replica figures without having to re-use any existing ARAH parts.
Hope that helps.