L.L.
I wouldn't be concerned that your little one didn't get this vaccine...it's not really a life or death thing, even if he does contract the virus. I am uncomfortable with this vaccine anyhow, because I have heard (maybe just rumors) that it has been linked to intussusception, which my youngest daughter just suffered. I don't know if they were linked, but still.
However, I would DEFINITELY be looking for a new pediatrician. I have never had my ped be "out of stock" of a vaccination that was needed...this reflects poor planning, in my opinion...they know how old their patients are, know when their vaccines are due, and ought to have enough on hand ahead of time. Especially if he has EVER messed up dosing ANYTHING! Scary! I hope you find someone new soon, but in the meantime, I wouldn't worry about it.