You could try sunrise hitek in chicago, I am not quite clear what you are looking for but we had them bid out some photos of athletes printed on sintra (a PVC extrude) and cut out. They might be able to print on other things as well. It's worth a shot anyhow. The owner is Jimmy Sun I believe.
I own a Roland printer that can create promotional graphics. It prints on graphics vinyls. The output has an adhesive backing and can be placed on any surface (car, window, plex/lex, etc.). There should be people in your area that can provide this service. They may be listed under Signs in the yellow pages because much of this work is just producing business related graphics. When you go to a trade show and you see all of the oversized graphics, you are typically seeing this output.
Might be an interesting alternative, but it sounds like a lot of work.
What this picture uses is individual shots mounted in slots so they can be moved or replaced easily. Figures are about 10" tall plus a couple of inches for base. Putting the cutout figures on clear plex means you can see the background and that there are no white or colored blank areas tio detract.
If I used the vinyl, I'd still have to cut out the pix manually, mount and then cut the plex on a router with a small bit--or with a good scroll saw with just the right blade.
It's a lot of tedious handwork for 17-20 images....
Graphics printers are combination printer/cutters ... so you get your artwork with precision cuts that are ready to use. The cut precision is amazing, but you need to prep your files in illustrator. Paths in illustrator become cut lines in the final work. They can be very intricate. When you mount a graphic use liquid mounting solution and a small squeegee to precisely position the graphic. Beacon Graphics is my supplier ... you might look at what they have to offer in terms of materials.