I would just use bleach on the inside of the coop and all food/water containers. The sun/wind/rain should disinfect everything else.
Eggcessive knows the real world stuff, I just read a lot. He says it may only take a few days for Coryza to die off when exposed to the elements, but there is no way to be 100% sure they only had Coryza. If their breath was bad and their eyes goopy then it most likely is Coryza, but they could also have MG, bronchitis, and/or other stuff that takes months to die off instead of days. So like he said, a necropsy is definitely warranted--or you can just wait until spring to get more chickens, which is when the chicks will be easily available anyways. I think that more than a few months of time should kill off every disease out there no matter what it is.
Actually I have never seen coryza or even MG before--I just read about everything I can read to offer help. Those two diseases just will last for 2-3 days outside the chicken. Simple cleaning the coop and equipment with 10% bleach water would be sufficient. Let things dry. ILT can last for months, so I would always recommend getting a sick bird tested or necropsied. If a chicken just starts out with bronchitis or some other milder disease, a secondary infection of coryza or MG can just make everything more serious. If there are any birds left that were around sick birds, they may just keep passing the disease along.