I bought a TELEX industrial headset on Ebay a few years ago for less than $20. OSHA rated for 23 dB noise isolation, which means I can't even hear phone ring when wearing it. Also has a noise cancelling mic which works very well. The audio quality of the mic is strictly communications grade- lots of low end roll-off and mid-range punch. It sounds rather harsh on FM and repeaters, but works great for VHF contesting on SSB- lots of punch, easier to get through than with hand mic. I had to build a little adapter box to use it with my TS-2000X, but all it took was a 1K resistor, 10 uF capacitor, and a PTT button.
Of course, depending on the model, might be harder or easier to interface with radios. Try searching the TELEX site by model number or series- I managed to find and download a schematic and spec sheet from Telex before buying mine. If the prioce is right, might not be a bad gamble to try one.
In general, I have found the TELEX headset to be very well built and durable, much more so than the specialty ham headsets marketed by some well-known names.
73, de Tom, KA1MDAwww.ka1mda.org