Sounds like a fun project. If it were me, I would find a large journal crank and get some MAP or carrillo rods. Either one of these pieces failing is just potentially too destructive to machine and your person to compromise. And yes, get the crank nitrided, though I don't know of anyone who will do it for $20. Trev, is there a place in OZ that will do it for $20? If so, I'll ship some cranks down there 'cause I looked around here in the US and $250 was what it cost me.
Other Trev: What is this one-piece crank? A friend here has what looks like a billet SJ A10 crank with the flywheel a part of the crank. What's the origin of this? Was it a racing item?
Anyway, Rocket Racer, as far as cams are concerned, the Megacycle 544-x3 is just phenomenal. The same profile in my A65 is, anyway. Doesn't give anything up on the bottom end but just builds incredible power and torque through the midrange up to as fast as you want to rev. I imagine for the A10 it will do similar things...probably much better than the 358 cam.