Honda VFR 750 Rc36/2 rear silencer seal

Moin! My machine is just in the workshop. It has been noticed that the cracker is rusted through and a used part has been ordered. When ordering the seals, the right piece for the rear silencer from Honda has not been supplied and on request the workshop has been informed that this seal is no longer produced. Where do you get new seals? Someone has had a similar problem lately? Solutions? Can other seals be fitted Being eaten? Would be very grateful about quick help!