I requested 2 metal bands with 2 threaded and 2 non threaded pins to replace the ones that rusted through.  The parts arrived today and to my surprise they included 2 sets of hinges and 4 latches with enough screws and nuts to replace all the hardware on one set of my dual composters. I am back in business.  I imagine I will have to replace the hardware on the other set of dual composters some day but I am confident that I won't have any trouble getting the parts.