RB- Agree with you and are handy, especially for quick inflation and doing many tires to air-brush work.

I lucked out years ago while attending a trade show in Chicago. Found a maker of miniature air-compressors so I acquired one of their sample units on the last day of the show. Crazy thing is there's not even a name or logo on it! Supposedly they make the mini compressors for specialty vehicle air suspension seats and guessing they were trying to introduce applications for other markets. Being a sample and they didn't want to bother hauling or shipping show items back, the price was nominal. The unit I have puts out high pressure but lacks volume, hence the needed air tank.

Anyhow, its super portable but because of the quality heavy build, the weight is probably 10 lbs.. Compressor is attached to a 1 gallon air tank with rubber feet on the bottom. Very nice quality. The compressor has rubber isolation mounts, has a regulator and can get up to 130 psi. The neat thing is it runs in both 120 volt AC and 12 volt DC. Has a fuse and auto-shut off pressure switch.

One could probably replicate and build one. Hadley (located in MI???) makes a good small 12v DC compressor and offers pressure switches. Hadley or a Taiwan made 12 volt DC unit with 150 psi and a similar air horn set-up shown below might get you in the right direction. You would need a small metal air tank (1 gal), fittings, regulator, etc.. For 120 volt AC, could try Radio Shack and find a converter to step down and change from AC to DC.