Wireless temp sensor & thermostat idea

Hi
I have an old thermostat controlling 1 zone with 3 bedrooms. I believe it was wrongly placed, close to the heat source at one of the bedrooms, which makes 2 rooms being overheated and one room staying cold. I was thinking to replace the thermostat with a new one compatible with a wireless sensor, so I can place the sensor at the optimal location. I would appreciate your advise! Do you know any brand / model number I can use?
Thank you!