I had similar work done on my .375 Ruger Alaskan by a local gunsmith. He didn't shorten the barrel though, as I liked it a 20." The work included glass bedding, installing a 1" Pachmayr pad without cutting the stock for a 14" LOP, removal of the front sight, threading 5/8"-24, installation of a new factory Ruger sight, and bead blasting. Price was $500-$600, but I don't remember exactly how much. Less costly than I anticipated considering the amount of work he had to put into it. He had quite the struggle removing the old front sight since he was trying to reuse it. Eventually he had to give up on that and order a replacement.