No i think it was a resonable price for the amount of work and the cost of the materials, he seemed very happy with it and made it as a side thing to his normal work, normally he makes stainless signs for the council so bending and welding a bit of tube was no big deal for him, what took the time though was making sure he had the angles and lenghts correct and when the final frame was made up he purposely left it to long and cut it down once on the boat before welding the feet that hold the front frame to the deck, and even once the frame was bolted in he needed to brace it on a jig and bend it slightly to make the gaps accurate each side, this was his first A frame but says he could now make others easier as he's had some experience making them now.
One other thing i wish i'd thought of....make sure the plate at the top is long enough to bolt at least two arials, a GPS antena and white light and have space left for a flag staff or other fitting, mine is slightly too small and means i'll have trouble fitting a second arial when i decide to purchase DSC in the future. Its not a major problem as i can attach it to the side tube as others do, but i planned the thing out thinking i had got it right and mostly i did except i should have thought about what i'd want in the future not right now !!
So if you do find someone who does stainless work then negotiate a good price and work out a clever design, mine came from looking at lots of A frames on ribs and i designed it to hang over the tubes as this makes the frame look wider as its a relatively low frame, also think about what it is you exactly want it to do and hold !! it does make the appearance of the boat a lot better and its great to see the way it turns out.
Let us know how you get on.