How much for 71 Thermoquad?

I routinely pay around $500. for just a couple decent old core And I
consider myself lucky.

They are a nightmare to find parts for and work on BUT = They are a bit faster
than the 72 up.

Any of the Newer Thermoquads can be modified and tuned to run
really well. If you do not need the last couple of Hundreds ET stay
away from the 71 Carbs.