I'm in need of a butt seat or back seat for a 2016 518C. while in a tournament my non boater used my back seat and the back broke off. the hinge is plastic and has been used very little. I've only sat in it a couple times. I really don't think my partner for that TX was leaning back on it when it broke, some other non boater may have cracked the hinges and it just let go on the last guy. any help with hinges would be awesome. thanks in advance. Randy