Hi sfbay,
I don’t know off the top of my head which ones make custom sizes but the manufacturers on the San Francisco list (which is the top part of the list) would be the most likely but you would need to make a few calls to find out for sure. There may also be others outside of the the list and some of the retailers on the list may also be able to order custom sizes from their factories but again I don’t know which ones specifically.
Phoenix