580D case backhoe

Hello everyone, this is my first post so I hope we're doing it correctly. We are looking for an apparently discontinued part for our 580D case backhoe or an alternative. The ring/seal between the exhaust side of a Garrett turbo and the exhaust elbow. The original part number was A155972 and the replacement part number of R51230. We have been unable to find anyone who can provide the part and ask for suggestions or an alternative, thanks.

580D case backhoe