The otter site has how to make the blade trigger same thing really.
http://www.ottersccustoms.com/trigger.html
Also dont get a new bolt. You dont need one. Unless your going LP then you do. But even still dont get a new bolt.
http://www.ottersccustoms.com/boltmod.html
That works almost as well as a 60$ bolt. Seriously...
Also make sure you polish the internals. Good stuff there.
http://www.ottersccustoms.com/polishing.html
Oh and PM on your price range currently and I will find a reg that suits your needs.