I suggest you search in salvage yards, we like Preferred Airparts and Wentworth Aircraft.
You may be able to find a turn coordinator or T & B at the Avionics Exchange page on Facebook, or at on eBay.
If you buy one from a private vendor get assurance that you can return it if it doesn’t work.
Well known vendors such as Aircraft Spruce and Specialty and Univair also sell instruments.
