There is a cheaper way of altering your cam timing. Turn your cam sprocket around half a turn, and then dial in your cam using a degree wheel and DTI.
Once your timing is where it needs to be, drill a new dowel hole in the end of you camshaft, and tap the cam dowel back into the new hole. It's not adjustable, (Although I did once do a multi hole adjustable cam sprocket, but the engine died a horrible death before I got the chance to tinker with the timing.