That 25580 inner bearing fits all Dexter axles from 5200 through 8000 pound and is pretty snug on the fit and wont take much misalignment while installing - and might even take a light tap or two.
If you have or can borrow a set of 2" micrometers, in and out, or better a
good vernier caliper with inside and outside capability, measure the spindle and bearing. This is the CAD with the dimensions;
https://cad.timken.com/item/all-prod...-2/25580-25520
If just a bit discolored with hammered in grease like I found one time, a strapping with wet/dry sand paper, using light oil as a lube may be the fix
Amazon has a bunch of verniers from low end to way up in price with the dial and digital kinda iffy until you get well up in price. Mine are the old fashioned kind that are tough for old guys like me to read without a magnifier.