Did you measure the body length including the boss? If so it should be 51 mm and is probably a 57BYGH51-602A and produces 100 oz.in (about 0.7 N.m) at 2 A. Your resistance and inductance figure aren't a mile off considering the quoted tolerances.

I know the voltage rating is higher than 24 V but, considering the reliability (or lack of it) of these boards I would be nervous of doing so. Some of the mods suggested on various sites are decidedly dodgy!

Russell.