Do you know a welder? I did mine myself its fairly simple. You can solder it if you like but I welded mine just to be safe. Take a 5/16 SAE stainless bolt, heat and bend it, I believe mine is about 85 degrees, not quite a right angle, cut one end about 7/16"-1/2" away from the bend, cut your bolt handle off, drill a shallow 5/16 hole in the bolt body, insert new handle to desired depth and angle to clear your stock, solder or weld it in, cut off the excess, grind the outside edge down to clearance for the mount, and attach your knob. I used a MFS 7.62x54R case for mine. I'll add pics in a minute