Not every machine shop has a truing stand to align in the wheels. You don't spin balance a crank after you split a crank, but truing it does bring it back to balance, if you didn't you'd definitely feel it shake.
A good machinist can break it and re-assemble it on his 20 ton press, and true it on lathe centers w/ dial indicators. But they are pretty reluctant to knock the wheels into alignment on their lathe. Otherwise, you'll have to find a motorcycle shop that does it and pay the price.
Nowadays, it's probably just as cheap to buy a complete new crank assembly. The old school art of building motors seems to be going by the wayside with all of the foreign parts and all.