While there are not many places to find examples of CHR for SWI-Prolog, searching GitHub does provide more than a short list.
https://github.com/search?q=use_module(library(chr))%20language%3Aprolog&type=code
Obviously I have not checked all of the noted code so YMMV.
These GitHub repositories are know to have quality SWI-Prolog code.
Also check out