-) transparency mounts with AN-glass:

GEPE
http://www.gepe.com/website/index.asp?pageID=234


Reflecta
https://reflecta.de/de/products/deta...00-Stueck.html


-) you may also try tension fixing mounts:

Diaspeed

http://www.apug.org/forums/forum45/1...nt-system.html