The hardware store

Currently I have no control over my thermostat or HVAC. I choose to get a wireless thermostat for my HVAC equipment. This means that my heater and air conditioner is controlled my a wireless remote. The remote turns on and off the HVAC. The remote can adjust fan speed, how much AC, and how little of heating as well. Everything HVAC related is centered around that remote. I can’t find my remote control though. I recently went through my home and cleaned it top to bottom. I vacuumed, dusted and washed windows. I also made it my mission to throw a ton of things out. I even cleaned outside and inside of my HVAC unit. I think it is possible, during the cleaning, I tossed out my remote. I had some many things piled around me to toss, it must have gotten shuffled in. I am hopeful that my climate control device is still around though. The reason is that I don’t know what to do if it is lost. Can I simply pick up a wireless remote at a hardware store? Do I need to go online and contact the HVAC business that sold me it? Maybe I can purchase a cheaper one online and have it shipped to me. Even if I do obtain a new remote, can it link to the thermostat? Maybe I need to do something special to make the new remote talk to the old thermostat. Knowing my luck I will need to replace the wireless thermostat too and have a HVAC contractor reinstall it.