WaMu timeline and compatibility?

[GDorsett]

I recently acquired a bunch of HO WaMu cars, most of them 380000s but I also have four 80000 cars. I know that the last of the 380000s were retired in 2006(8?), however, I do not know anything about the 80000s except that they preceded the 380000s and have an older bearing style. Can I run them in a train together behind a JRF loco?

And could I kitbash myself a WaMuFu out of one of them and keep it prototypical, or were those phased out a while ago?