Lou, I don't know about a list, but Revolution makes a good folding cane. I use theirs pretty much full time. Here is their contact information.
Revolution Enterprises Inc. 12170 Dearborn Place Poway, CA 92064
Phone: 1-800-382-5132
Fax: 1-858-679-5788
Regular phone: 1-858-679-5785
Contact Maressa Fox for cane orders
I never had any success dealing with California Canes. Their canes often broke, and they seemed reluctant to either give refunds or stand behind their products.
Harvey