My setup is similar to yours. I have a 160 PSI/26 gal. oiless shop compressor. The working line on that is normally 120 PSI. I have a second regulator with filter and water trap that feeds the airbrush. So far, a 0-50 PSI gauge has worked well for me. It's not very big, and my eyesight isn't what it used to be, so I'm thinking of a bigger gauge. But other than a minor visibility issue, it's worked great for years.
I don't recall using anything more than 30 PSI for my airbrush, but I wouldn't take that as gospel.
I'm really liking this Sears oiless compressor. No maintenance, and it delivers very clean air. My paint work has improved considerably since I replaced my old compressor that did use lubricating oil.
One alternative to consider. My friend who uses her airbrush professionally, swears by a 25 lb CO2 tank. Totally quiet, completely clean, and compact. She refills it once or twice a year. I'm considering repurposing my SCUBA tank like this.