I got a carter 9635s , if you are interested I'll dig it out and check the condition . Its in a separate building and it snowed here this morning , will it ever quit .
Did some research the 6710 and the 6210 have the same throttle bore Pri. 1 3/8" , Sec 2" so you may be right the difference is in the venturi Sec. 6710- 1 23/32 and the 6210 - 1 3/8 the Pri. venturi are the same 1 5/32 . PM me and we do some carb parts trading
I got [ 4 ] 12R 5395B baseplates which were a 6210 carb , 650 cfm . 6710 carb baseplate is a 12R-5768 , 800CFM I don't know if they work . But while looking found a 6211 carb which was 800 CFM baseplate 12R 4926 . with out comparing them I'am concerned it may not work for you
I have a carter 8001s , for a 318 cu.in. $35.00 plus $20.00 shipping , I calling this a a very nice ,clean , good to be rebuilt carb .P/M if interested.
the only carb I know of with the metering blocks you want would be a R-8156 ,Pri. 8542 and sec. 6541 blocks . I will check my stash but I really really doubt it.
if its a carter model bbd echlein #2-4815=kem cp152,hygrade cpa-64, holley 9-213,niehoff fs-18,sorensen cp-136 according to my old interchange books.hope this helps,if you still need one i might have one nos