Carburetor change out recommendation

[Cream Puff]

Hello everyone! This is my first post so be gentle
Cream Puff is a 1968 c10 with 292, straight six engine, 63,000 original miles. I got her from a neighbor who inherited it from his late grandfather from Oklahoma (he was the original owner.)
The truck sat for 5 years with a full tank of gas. The seals were bad so I went ahead and had the engine rebuilt since we were going to be that far into the engine anyway.
My problem is the 1 barrel Rochester carburetor has been rebuilt twice now and it is still giving me trouble. I now think it is one of the passages way down deep and I am ready to replace it.
Q.I was wondering if I could get some advice on what type and or size carburetor you would recommend for all around performance? The truck is completely stock and I want to keep that way as much as possible, but am willing to change out the carburetor.
Thanks for your help.

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