Short answer - no and no!
Long answer - you shoud not attempt to straighten a bent crankshaft EVER. All sorts of internal stresses will be created, so even if you do get it straight, it will be likely to 'let go' explosively the next time you hit anything larger than a pebble.
In theory, you could replace the crankshaft, but the RV150 is a Chinese copy af a B&S Quantum, and the factory simply don't produce spare parts, as the wholesale price for a complete engine is so low.
If you want a replacement engine, let me know.
phil_saunders@bigfoot.com
Phil Saunders, May 2008
