.....bad Don you can't come up with a piece of small railroad rail, mill some grooves in it, parkerize it...and have an authentic Picatinny rail.
Well, actually, I have several sections of old track laying around. Anywhere from 12" to 36" long. A bit heavy to get in and out of a forge to hammer in the bevels, though, so I'd have to go with modern machinery.
I should get hold my machinist friend and ask him to mill the grooves down the length of the 36" one, but I don't think I could do it with a straight face! Then again, he's used to me asking for help with odd things...like breech sections for 6" cal mortars and such.
I get in enough trouble using my wife's good stainless pots for parkerizing knife blades. She'd kill me in my sleep if she came in and found a section of RR track on the stovetop!