Yeah, the modulus stock is probably your best bet. The raider stock is really comfortable, and you don't want to change that. Plus, the modulus stock gets great ranges. I can't think off the top of my head how to make the raider stock into a gun stock without serious mods. If you want my opinion, get the modulus stock.
Wait, I just thought of something. It would require filling in the holes that you made, but you might be able to use a jolt handle. This would require locking the stock in one position though, and that may be annoying. If you cut stick a jolt in and extend the barrel, with a bit of drilling, you could turn it into a stock similar to the modulus one. Sorry if that's unclear. I can't figure out how to post pics.
Sorry I haven't replayed in some time been busy with life... Blah...
The modules stock is nice, however what I was trying to achieve with this is to take an ordinary stock someone wouldn't think was a blaster and make it one, something simple, cheap and easy to make, while maintaining the secrecy.
I've almost finished it when I was filling in holes to try and reduce leaks and filled in the wrong part now the collapsible part doesntvslide so good. Need a new stock. But I know exactly how to make it now and plan on getting the parts to remake and will be posting a full write-up on it. I think people will be impressed..