Will these casters fit on a Manfrotto 190XPROB tripod for a DSLR ?
They will fit any circular tube of 22mm. I don't know the diameter of the 190xprob lower legs, but I expect Manfrotto probably publishes those specs somewhere.
For what it's worth, I don't think I'd put anything too heavy on that tripod with casters on it. It's really not designed for it, and I'd expect the rolling motion would put additional stress (the engineers didn't expect) where the legs attach.