Here is an update, Mistress Mercer had a studio in Ashville, NC and has a place in Myrtle Beach. She lost everything in NC with the hurricane, including the shop where she did her welding. I've heard this second hand. I do not know here but we have mutual friends. Everyone I know thinks highly of her, both the quality of her equipment and sessions.
Here is a link to her websiteYesGoddess mentions Metal Bound in South Florida. Years back, I visited their shop and ordered custom equipment. The pieces they had on the floor were of quality and very ascetic. I wasn't impressed with the custom order, which was late or the customer service. That could be an isolated case. This was some years back. I don't know what you are looking for in equipment but, even though I can't rave about my experience, the quality of what they had in the shop was excellent, if the design is your cup of tea.
I haven't heard back from my friend in Dallas about the kink welder he knows yet.