Is it uncommon?

Is it uncommon or difficult to find a true and pure Suriname red-tail boa at a reptile show?

What other "TRUE" BCC's would you recommend?

I saw a Guyana Bcc at the last reptile show I went to.

I dont know about the availability over there, but i would recoment to take proper investigation to recognise them better, and to contact a breeder witch you are sure to breed pure animals...

Guyana and surinam are practicly the same looking snakes.
Then you got brazillian, witch i think are the most amazing redtails.
Peruvian is also quite commonly seen, they get really huge and yellowish.

BCC are a lot more difficult to find as opposed to BCI, it'd be worth it to find a reputable breeder so you know what your getting. Suri's are my favorite BCC, but I love them all, gorgeous snakes.