I installed a new speedo cable in the Mule last Saturday prior to selling it. I got one from CCOT which was MUCH cheaper than an oem unit and it fit and worked great. I would suggest getting one of those before putting in another used one.
I thinking someone else suggested it but pull the internal cable all the way out of the sheath. That will tell you if it is broken or not, you can also inspect both ends closely at the same time. Lube it with something when you feed it back in.
Randy Rosetta KDØKWX TLCA #19351 69 FJ40 "Meanie" & 1970 Boss 302 Mustang