Hi Andy and welcome to NeuroTalk! Happy to have you here - not for the reasons you stated in your post, though. I do hope you can find some relief and answers. I can relate to the numbness as my right arm and hand is numb (I have MS) and has been for 9 months.
I see Koala has provided you with a link to the Stroke Forum. I hope you visit there....possibly someone there has heard about the Thermal Stimulation and can advise you on it.