I need some help from you experts out there. I own a pair of old Sony U-Ceiver ICB-U655 walkie talkies. They have a 2-hole port on the top that appear to accept a 2-prong jack from a headset. I want to get a throat mic setup for my radios, but I’m not sure about the compatibility of certain mic setups with my old Sony’s. So many mics say specifically for Kenwood, Motorola, etc. Can anyone tell me if any headset/mic setup out there would work with my radios, or am I going to have to get new radios to have a throat mic setup? 
This is an older FRS radio circa late 1990s. According to the user manual it takes a CBM-20 Sony Speaker Microphone. According to the specs on the CBM-20 it’s a stereo mini-phone 3.5mm connector. You would need to experiment with a few headsets to find out if one or more would work with the radio.
It depends how much you are willing to invest to find out. FRS radios have come a long way since then. Power management is better and they have features the Sony doesn’t have that could be useful. A lot of new models include headsets. Personally, I would just go with new radios with accessories that I can easily match to them, but that’s just me.
Just to chime in here, but I would agree with Rick on this one. Anymore a new set of radios with mics included is often just about as expensive as buying mics. And for that extra $20 you get brand new radios that you know will work with the mics. Save yourself the aggravation and hassle would be my advice. If you’re determined to use these ebay may be the place to look for headsets matching the pin set up, very little stores by me carry headsets anymore.