Not something I've had a lot of interest in, but I picked up this well circulated example today, a 5 Pesos note known as a "dos caritas" ("two little faces") type. Here's a good website on this topic: http://papermoneyofchihuahua.com/ Does anybody out there collect these? It'd be something of a challenge to obtain all the different bank and state issued varieties of this period.
Just to finish this off, here's the "Veinte Pesos" variety which I happened to run across today in uncirculated condition. As you can see, the designs of all these are essentially the same.
