$500???? Yikes. Sounds rather high. Maybe he's high!
Typically if a crank is cracked, its no longer in one piece. Not the same for heads and blocks.......
Make damn sure the reluctor ring is not bent. Just have them check the big ends of the rods. You cant resize 'cracked' rods anyway. Polish the crank if necessary.... and away you go.
LS6 cam is nice addition as well. They are fairly inexpensive in comparison to new cams which are $350 or better. I even think I have an extra one..... let me know if you are interested and I'll see if I still have it.............
Jay