I got this one here - https://www.amazon.com/Arthritis-Trigger-Carpal-Stabilizer-Tendonitis/dp/B07CX4CX96/ref=mp_s_a_1_68?keywords=thumb+spica+splint&qid=1673410043&sr=8-68

And then when I was feeling a bit better after about 3 months since I was diagnosed, I started alternating with this (usually used this when going out of the house) - https://www.amazon.com/Futuro-Stabilizer-Improves-Stability-Stabilizing/dp/B00CREYMW4