Here - I've got some pics. I made about half a dozen prototypes and I kept them but didn't photograph them.
I will make these to order for anyone who's interested. I am going to use different metal though because I find this type too thin for the rails it's supposed to slide into.
I can make 'em for $30.00 each shipped. If there's enough interest I'll make a trip to the metal warehouse and see what they have in a thicker stock.
I tried to order a replacement plastic selector switch for my MP40 but they're hard to get too.