Would definitely recommend jumping on E-Bay and buying an NOS "Made in US" pump, then run ethanol-free fuel, if possible. I'm running fuel injection now, but when I was running a Weber I had an NOS pump on the car and another NOS unit on-hand as a spare, both from E-Bay. You'll pay a few bucks more, but it seems even the "cheap" US-made aftermarket parts from the 80s/90s are still superior.
The generic Carter/Advance/O-Reilly's/RockAuto pumps all hail from foreign shores and quality seems questionable at best.
Anymore, I feel good when I'm able to find Mexican-made parts, just to avoid junk from China. Pretty funny, because it used to be that Mexican stuff was the worst, but a lot of Chinese aftermarket parts have since set a new low.