I am lucky enough to get my hands on a Realistic TRC-86, the walkie talkie they used in the series. Not sure if it works but just to have as display is
Realistic TRC-219 21-1639 3-Channel Transceiver for sale online | eBay
Authentic 1980s Realistic Brand TRC-88 Walkie Talkies by Radio - Etsy Canada
Vintage Walkie Talkie - REALISTIC TRC 219 used by Mike Wheeler (Finn Wolfhard) in Stranger Things | Spotern