Where to buy a 5x7 contact printer for glass plates?

I recently did a wet plate workshop, producing both 5x7 tintypes and wet plates. I don't know if this is something that I will ever be able to get into here in Japan but regardless, I'd like to get myself a 5x7 contact printer so I can make some darkroom prints of the glass plates. However, I seem to have a hard time sourcing them. There are some vintage ones on ebay, but they are pretty pricey (although I guess if I never do wet plate again I could use it as a frame). It seems to me I had a link to a store that sold these types of contact printers, but I can no longer find the link (or maybe it's all my head). Either way, looking for suggestions about getting one, outside of making one myself.

Photographer's Formulary have offered 8x10 contact print frames, but all of their sizes seem to be out of stock: http://stores.photoformulary.com/contact-print-frames/

You really only need a contact frame for alternative processes where you open part of the back to check exposure, thinking Albumen prints and similar which have no development. Just use a sheet of glass, I have a pice of 1/4" thick glass somewhere that I used to use for contact prints, it got a bit scratched but my glass supplier could cut me a new one from his scrap pile

Ian

Do you need glass if you are using glass plates?
You cant just use a normal picture frame with a few clamps? Thats all I do. If I need to check I just carefully tape the bottom of the negative to the paper.