The 1953 216 and 54 235 high mount pump has the narrow belt pulley. If you're familiar with water pump construction, it's not too difficult to modify an off-the-shelf later model pump to the short shaft configuration, since you've already modified the radiator mount. Just press the fan/pulley mount back the right distance, and cut the shaft off to the correct length. Be sure to support the back end of the shaft in the press firmly so the mechanical seal isn't damaged while relocating the flange.
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!