Hi, Abby. I'm glad you've been feeling pretty good.
Why don't you put a coat on and sit in the sun in the fall and winter?

I try to do that, even if it's only inside in front of a window.
If it were me, I wouldn't want to risk the immunosuppressant/sun cancer possibilities. And light therapy has the same risk, whether it's a tanning booth or one in a doctor's office. In fact, it might have more risks due to the fact that it's not a "natural" light source.
Have you tried upping your D dose or trying a different supplement?
I feel better in the sun, too, but, for me, it's probably only a mental improvement after being cooped up. Although I have to say that the more "energetic" areas on the planet (look up ley lines), as the one in southern FL, make my mind feel amazing.
Annie