Got any part numbers available? I can't imagine a reason for that much price difference, particularly for the same charging capacity. There is a heavy-duty double contact regulator, but it was designed for use with the 50-55 amp Oldsmobile and Cadillac generators with ball bearings on both ends. As long as the current regulator can control the generator at 30 amps, I'd pick the lower-priced regulator for my own use. You can replace it three times for the cost of the pricey one. Regulators just aren't that complicated! Is there a different warranty, maybe?
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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