Best quality for money is buying a single reconditioned Motorola XTR446. Look on fleabay. Or a 2nd hand one. They're also very rugged.
Z-Tactical Bowman EVO III headset is a good choice & a Z-Tactical U-94 PTT with Motorola single pin connector (2.5mm)
- you should be able to buy those together as a deal cheaper than separately.