The original Chrysler choke # for a '71 & '72 340 intake was: 3512875
and the Carter part # was: 170-148
The Carter # you have was originally for a '72 400 big block but is inter-changeable with the 340 #.
The Chrysler part # for '71 & '72 intakes is NS-1, meaning the choke is no longer avail.
Your carb to intake gasket does not require an additional thin upper and lower gasket; the original was made from Aluminum and was slightly thinner and used an upper and lower thin gaskets.
You will have to repair yours or find a good used or NOS choke, David.