If the regulator you found looks like it's not damaged, go ahead and try to use it. Just be aware that most of the aftermarket replacements (then and now) don't measure up to the quality of an original equipment Delco unit. I'd rather have a good condition used Delco regulator than a brand new no-name item. At least I know I can service and adjust a Delco- - - -I've been doing it for close to 60 years.
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
Love your enemies and drive 'em nuts!