Thanks for the intro Froggie.
A friend wants the same thing as Lorrin. Working on one now. Start with a stainless .22 Super Single Six, it has the adjustable sights. Shop for a used or take-off stainless .32 mag barrel and cylinder from the Ruger Vaquerito, they were made in stainless but only with fixed sights. Either put a brushed finish on the barrel and cyl or polish out the stainless .22 so they match. File the front blade sight off the .32 barrel. Unscrew the .22 front ramp sight from the .22 barrel, drill and tap a hole in the .32 barrel and screw on the sight. The .22 ramp sight is a smidge shorter, so if the adjustable rear sight won't go low enough, order the .32 ramp sight from Brownells or Ruger.
Lower the firing pin in the frame for the center fire .32 thusly:
In the 1st two shots of a converted old model, you can see where I plugged and re-drilled to lower the firing pin and recoil plate for center fire.
There's a firing pin recoil plate retaining pin thru the frame under the rear sight. Remove it by opening the loading gate to drive it out to the left. Now you can drive out the firing pin, spring and recoil plate from the hammer channel. Make a plug .001" larger than the size of the recoil plate with a smaller diameter tip on the firing pin end to fill the hole in the hammer channel. Take dimensions of the firing pin hole because you're going to drill another one just like it. Pull the barrel and drive the 'plug' into the recoil plate hole. Screw the barrel back in hand tight.
Now with a 'range rod' that's a snug fit in the .22 barrel bore and has a sharp point on one end, drop it into the bore pointy end first and center punch a dot on the recoil shield (breechface) at the back of the cyl window.
Pull the barrel and drill a hole the same size as the original for the rear end of the firing pin all the way thru the hammer channel. Now use a Letter 'J' drill to counter bore the firing pin hole for the recoil shield to the depth that you measured the original hole. About a third of the plug will be drilled out as well.
Install the firing pin, then the spring and the recoil plate which is a press fit, and drive into place flush with breechface. Now drill thru the retaining pin hole and reinstall the firing pin/recoil shield retaining pin which will actually retain both the plug and the recoil shield in its new location. Ruger designed the new retaining pin hole location so it would work for rimfire or centerfire recoil shield locations.
Fit and install stainless .32 barrel and cylinder. Had to enlarge the loading gate chute slightly for the larger .32 case rims.
It's a 1 hour job after doing a few of these. Now you have a stainless .32 H&R mag single six. I will also ream the chambers an 1/8" for the .327 Fed Mag like the old model shown above.
Isn't this something you have done already, or did you go with blued steel instead? As long as one were staying with a 32 H&R almost-magnum and not going up to the hotter loads some folks have cooked up or the longer 327 Federal (true) Magnum, the little Single Six platform should work quite well. 
