Hey mykeal,
I know O.S.O.K. replaced one of the springs on his with those. You might want to private message him?
Also, I believe the spring is actually the spring for a Colt SAA. If you look under parts for those I think you will find it.
I think this is it:
http://www.brownells.com/aspx/NS/sto...%2fBOLT+SPRING