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
RadioPics Database - CB Radio - Realistic TRC-219
Vintage Walkie Talkie - REALISTIC TRC 219 utilizado por Mike Wheeler (Finn Wolfhard) en Stranger Things | Spotern
Stranger Things Realistic TRC-218 Walkie Talkie Two-Way 2-Watt 3-Channel Radio inglesefe.com
Pair of Authentic 1980s Realistic TRC-219 Walkie Talkies by - Etsy
Vintage Realistic TRC-219 Handheld CB Radio Walkie Talkie Stranger Things – CDE
WALKIE TALKIE STRANGER Things radio CB portátil vintage realista TRC-219 EUR 50,17 - PicClick ES
Vintage 1980 Radio Shack Realista Walkie Talkies Stranger - Etsy España