McM will do a stock for you for a Ruger, but be prepared for the sticker price, as well as a LENGTHY wait time to get it (I think they are running ~9mos on some orders now, not to mention a custom inlet for one of their tactical stocks). I know that Dick has said that they can at least do SOME of their tactical lineup for Ruger actions, but you'll likely have to give them a call to discuss options, pricing, lead times, etc. In addition to a custom stock from McM, and the garbage from Boyds and Hogue, HS Precision also offers at least one or two options for the Ruger M77, MkII actions (not sure if that'll work for you as you didn't specific whether you had an older, tang-safety model or a newer MkII in your post).