Is $1,300 to replace equipment interface module a fair price?

My humidifier line broke and sprayed water on everything around it which included equipment interface module. It mostly shorted it. Now my thermostat flashes E1 error and no cooling happens but furnace runs fine. I called HVAC guys, he diagnosed and said my interface module is shot and needs replaced and quoted 1300 for it. It's a Bryant thermostat. I am wondering if this is reasonable, if it's something I can buy off market and install myself, if it's simple as unscrewing and screwing parts, or if I can bypass and get another thermostat as I was planning on replacing it with ecobee anyways. I have two furnaces up and down. I thought this was a standard thermostat and didn't realize it might control humidity, although it has a humidity option that never did anything. I recently moved to this house. I'm assuming the control module and thermostat go together and am wondering if I can replace both with something newer.