As Luis pointed out, the paper is used for pirnting maps. During my search, I
found that it was also used in durable packaging, so you can check with local
printers that do this kind of special printing to ask if they can sell you a
few sheets.
Ironically, while the paper is made in Michigan (where I live), I found that I
could buy it at a cheaper price even if I buy just one sheet in Indonesia
(which is literally on the other side of the world), but I don't know anybody
there, so it wasn't convenient for me.
If you search the Web, beside searching for Kimdura, try also "synthetic
paper." There are a few other brands, but they are equally difficult to buy in
single sheets.
Dave S.