Yes, the fork in the second link is made by me with Kaisei (Ishiwata) tubing.
It’s unlikely an autopaint shop will do a nice job on bicycle frame unless it’s something they do regularly and/or have an interest in bikes (the care factor will be low). Are you guys talking about masking BB threads and reamed insides of HT and ST? This takes 5 minutes, and any autopaint shop should be able to do this without jacking up the price. It’s masking of lugs and 2 tone paint etc that takes time and practice.
I wouldn’t take a frame to an auto shop for a “nice” job, although with the proper instruction there’s no reason they couldn’t do a reasonable job. Ran into a friend of mine yesterday with his airbrushed frame - super nice.
Airbrushes are good for home paint jobs and applying base colours - easy to control where the paint goes and less likely to get runs - but I don’t think it’s possible to get a rich glossy clear onto the frame using an airbrush? - clears need to be flowed quickly to avoid overspray and dull spots.
Try Fleming Jensen at Bicycle Recycle in Moorabbin - he’ll do a strip and single colour for about $140. Also Jon Weaving at Gripsport in Research - will strip and powdercoat in a single colour for $105. I’ve had frames done by both and have been happy with the work. Short of buying a rattle can you’d be hard-pressed to get a pro to do it much cheaper.