It looks from your scans that your left IJV is dominant. I made this judgment based on the apparent width of the left IJV compared to the right side. I agree that your right appears to have significant compression that’s predominantly caused by the transverse process of C-1, however, the right styloid also appears to be contributing to some degree as well. Based on this information, I think Dr. Costantino would be a good choice if you decide on surgery though a consult w/ Dr. Hepworth would also be worthwhile.
We have some members who’ve been treated by AO chiropractors & have had their C-1 vertebral position changed but this can only be done to a very small degree. I don’t think any of them received vascular compression relief but perhaps did get some relief from neck pain/tension. You can search AO chiropractor using the magnifying glass icon in the upper right of this page. Here’s one link: