Here is the air inflator/guage I use
https://www.kleen-ritecorp.com/p-2036-acme-tire-inflators.aspx
Never had one taken, they last about a year. I just use a basic rubber hose and repair replace as needed. I like the retracting idea, just seems pricey.
I hate paying for air, and was reluctant to add a pay air station. With the toggle between air and vac I feel like I am offering an extra service for same price as vac. I have this just on one vac and it does get plenty of use.
A stand alone air station seems very pricey, and would take a while to recover expense. I have not researched this, but I bet one could somehow mount a small compressor in perhaps a partitioned area of the vac debris area if a line can't be run from the main compressor...likely would be less $ then the air only unit. I did add large decals AIR decals on the vac dome.