That kind of polishing was routine in the 50's and 60's due to the popularity of sporterizing military guns. However those days and gunsmiths are gone. Most of today's gunsmiths lack the skills and equipment to do a proper job. That is why painting and plating is so popular. About the only way to get it done right is to find a dedicated refinishing shop like Ford's, AP Cogan, Robar, etc. A restoration shop like Turnbull is also a good source. The problem with gloss polishing is that it is labor intensive with a lot of handwork if you want to preserve sharp edges, unsaucered holes, flat flats, round rounds, unpulled lettering, etc. Far easier to bead blast the crap out of it, spray it with Cerakote, pop it in the oven. Done.
RAN