I bought one like this from Amazon: https://www.amazon.com/United-Ortho-Plantar-Fasciitis-Splint/dp/B07CD185S3/ref=zg_bs_7491807011_14?_encoding=UTF8&psc=1&refRID=DVGZ2MTC589XF81FVV0Y It’s not the best quality (one of the straps did break) but it does the job pretty well, and you can adjust the straps if you want more or less of a stretch. It says it’s made for plantar fasciitis but it works well for ankle stretching too