Thanks for the information. I guess I know enough now to get the correct board at eBay. Unfortunately, I will still have to ask the sellers to do separate screenshots without the B board on top because otherwise I can't see if it's the 10 Hz or the 12 Hz version.
@Marcelo_20XX:
An unrelated question: The game at your local arcade, is this really specifically version 910206 of "Street Fighter II" and not just any revision? Did you see the number on the screen?