I don't know if you have to cut him down for accupuncture, but if he's getting warm due to the warmer temperature, maybe a puppy cut would be good for him
And you're right, a t-shirt of some pj's would keep him warm if he does get cold. I'm so happy that he has actually stood up for you and walked a bit!!! I hope this accupuncture is just what he needs to help him have a full recovery. I'll be praying for your sweet little Babybear!!