Go to cheaper than dirt , item # GSN-001 . This is the SR300 bench rest for just under 40 bucks. Does the job real well for your ruger .It ain't a world class rest but does the job. I use a 35 year old rest somewhat like it at our club /fun matchs and allows simple vertical ajustments. Then buy a standard rear bag and make up several square pieces of plywood with dowels that can help control a stack and spay glue some rubber to the top to control your rear bag. You can just cross tie some rabbit ears on it or make up a slide support to bolt to it. Depends on your stock profile. I have a bolt and a 10/22 and can shoot in the .250 to.300 with mine at 50 yards and don't place near the top but the couple other semi-auto guys and I compete against each other. I to have some kidd parts .