Do you know if the spark plug came out from damaged threads, or possibly just unthreaded itself? I recently retired after the past 23 years at a Toyota dealership, and can not recall ever having a spark plug come out from damaged threads, but did have a few where the plugs had been replaced, but must not have been tightened enough. In each case, I was able to just either put the same plug back in, or if it looked questionable, install a new plug. Unlike my Ford V10, most later Toyotas have long threads for the plugs, close to an inch long, so chances are they threads are fine. I would just try to put it back in, snugly, and if it damaged the coil, install a new coil.