Belt drive parts
"But with that said belt-drive Whirlpool parts are now fast becoming NLA and now is the time to stock up on them because they will be like Unimatic parts soon, gone for ever!"
To WP's credit, the fact that they used the same basic mechanism for SO long and that KM in particular was SUCH a good seller means that there are TONS of new and used parts out there, as well as machines to cannabalize if necessary. Unfortunately, this can't be said of other manufacturers like Frigidaire, Speed Queen, who kept switching mechanisms every so often. The "Champions of Design Longevity" other than WP, seem to be Maytag, Norge, & GE, which makes older models much easier to restore and even upgradeable to better than original.