I believe any Torrington needle bearing of appropriate size can be incorporated into a shaft/carrier assembly that can be pressed into a pump housing. Instead of using pre-lubed sealed bearings, I'd probably drill and tap the pump casting snout for a grease fitting so the bearing could get a shot of lube periodically. From there, it's just a matter of fitting a mechanical seal to the coolant side of things and a pulley/fan flange and an impeller. With some careful disassembly, the flange and impeller can probably be re-used. I'd probably make some sort of puller to remove the impeller from the back side by drilling and tapping a couple of holes into it so a puller could be used on it. I don't think two or three small threaded holes would affect the performance of the impeller.
Jerry

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