I don't know what Tengujo is, but Tyvek is both strong and thin and might work well.
It's Kozo paper. Check it out here. http://www.japanesepaperplace.com/retail/retail-products/tengujo.htm
margaret alberta
I have been running some experiments repairing popups devices in books. and i have an idea what i want to run past someone else before I try it.