They come apart pretty easy. Press out the 2 bearings and you have the housing to refinish. Pulley, nut, screws and windings are straight forward. Throw in some new brushes and you should be good.
My only point is that they are not all that complicated. If you have a correct working unit, it's not too bad. Restoring all of the pieces has been discussed here many times. Much more complicated items have been detailed here on the restoration process. I see many of the NOS parts around. From what I recall, the final details might be the ink/paint stamp and the dye mark on the numbers. Either way, it's good to support our restoration vendors when possible.