Wow, fascinating! Pure speculation, but I'm guessing age is between late 1800's to very early 1900's because pics I've seen while googling show this brand of chair dated newer (1930's-50's) are vinyl(?) and chrome, not leather and wood like yours. Try googling "kochs barber chair" for more info, one sold for abt $500, one is one eBay for $4000, there are lots of them out there but I haven't seen any (yet) that look to be as old as yours.

That is a c.1903 Theo A Kochs Columbia chair. The original patent is date 1898. There were a few changes between 1898 to the 1903 models. I have an 1891 missing the headrest and footrest. I have been searching all night for photos of the footrest and here you provided a nice closeup. All I need now is to find a photo of the backside of that metal plate. I have the wooden piece that goes with it. Hoping to get enough pictures to see if I can have someone build me a temporary replacement.

I have added a link to the patent for that chair you have. Biggest difference is the base. If I find the patent for your exact model I can e-mail it to you.

Martin
mnieves79@hotmail.com

Here is a link that might be useful: Patent 598877 (Feb 8 1898)

Sorry, its not a Columbia. It's a Kochs' Gold Medal from Theo A Kochs & Son 1903 catalog

We just finished restoring an 1898 Theo A. Kochs barber chair. It was missing both footrests, so my husband made just the bottom one of polished aluminum. If you would like to see pictures of it email me at grannybrenda@msn.com.
Also if anyone has the footrests and is interested in selling them please contact me at grannybrenda@msn.com.

Trying to figure out age and value on this old Theo Koch barber chair ..
Also where to sell it .
Any help is appreciated !