If you cant find anything, you could just get some ankle braces on amazon.
I've used this one in the past while working in the kitchen. It's decently priced and probably provides better support than a boot would
I used to think that when a military accident tore up my ankle. These put me back on the mat. :).
Med Spec 264016 ASO Ankle Stabilizer, Black, X-Large https://www.amazon.com/dp/B00TZTO19I/ref=cm_sw_r_cp_apa_i_JobIDb0BZR266