There are several flying P-51B/C in the US.
The P-51C was the designation for a P-51B built at the North American plant in Dallas.
The real rare bird is the P-51H, a lightweight high performance variant that only shares about 10% of the components to the much more common P-51D.
Only a couple still flying.
I did see a “B” at Osh kosh a few years ago, on the static line.
yeager and anderson were there that day, flying, but they were flying “D”s
not sure I have seen anything other than a “D” in flight, but then again, I dont get out much. :)