I clear-coated my handle after sanding it. It sanded pretty fast using a dremel rotary tool. I also took the time to fill in the left indent with epoxy (clay-like epoxy, not liquid). I gave that epoxy part a shot of silver spray paint and it matched the rest of the handle very well.

My preferred fascia would be clear aluminum. Either clear anodized or clear-coated. Either shiny, or perhaps brushed.

Price.... That's difficult. I don't want to suggest one because I don't know how much it's going to cost you in the volumes you'll be working with. I'm in a money crunch and don't really have any room for toys right now, but I'd always appreciate lower than higher. But I think you deserve to be compensated for your time and make a nice profit for your work.

If I could make a few suggestions for your design (or requests), the first would be to allow using the default MK2a buttons (the pointy ones). The next would be to contour the part of the face that wraps around the knob. Make it round instead of coming straight down on the sides. I made a quick sketch long ago on paper that looks pretty good - mostly similar to your design (clean and simple).

I'm really glad someone has renewed interest in a replacement face. It will make the empeg that much more solid feeling. Right now the plastic fascia is no doubt the weakest-feeling part.

Bruno