Maybe check with Charlie/NY on this forum? He'd be the first one I'd call.
FWIW
I tied to find ethanol friendly rebuild parts for my Stewart Warner electric pump without any success......plenty of "original" parts available, but those will fail again with ethanol laced gas.
Yeah, todays fuel mixtures are a cause for concern. I used to use these old pumps, in the old days and they did a good job. Just hate to trash good old USA made parts. Guess I'll just go with newer smaller units.