We'll test soon Tepede's backlit film (www.tepede.nl) and I will tell u is it OK. The guys from Tepede have 10-12 materials, compatible with Seiko CP64s. Go to www and read.
I would suggest you call DGS (305) 628-8345. They have a very nice film that Seiko prints on at their own tradeshows and backlit diplays in their tradeshow booth. Contact Mr. Roberto Rodriguez.