I am presuming you are looking for something like the hard chrome finish on the kel tec. That was done in their factory as a finish they provided. I'm not sure you can get an exact match without having it professionally refinished... hard chromed with matte finish... but then that's what you would get with Taurus' stainless steel slides. My guess is it would probably be cheaper to just buy a gun with a stainless steel slide.
The only other approach that wouldn't cost most of the expense of buying another gun would be to find someone to do a duracoat finish. They make a metalic stainless steel finish which should cost you less than $50 for the slide. They also make their finishes in a multitude of colors so you could reporduce the new OSS color scheme (their finishes will bond to polymer as well as metal).
Or you can buy more dremel wheels and polishing compound and keep yourself busy for the next few months.