I have a couple of those that I got for a little over face ages ago (and that's about what I'd pay for them now). One is Yellowstone and the other the Grand Canyon. They are (or were) produced by the New England Mint
. I'm not sure the company is in existence anymore as the e-commerce part of the web site is broken. The notes are legitimate United States BEP currency that have been colorized aftermarket.
Worth anything? Collectible? Well, collect what you like but the fact that they've been colorized turns off many collectors. However, certain people do like them. A quick search on ebay
shows that you can buy one shipped for $12 (or up to $25 if you really want to spend the bucks).