Let me know when you need the cheese.
I can't remember, but it seems like you have a lathe or access to one. If you do, can you put the blanks between centers and measure the run-out at 12 inches from the joint end? To me, that would be the best way to determine the straightness of each blank. Might even ask your supplier to do this before you buy to determine if they are all straight. The size is right at the final pass stage for most of us, so there is little to no margin to work with if a blank has a big hop.