Problem with 3D printing is you need an accurate 3D drawing of the part. Where you gonna get that?

Great Plains has a newer design phase plug based on the Tangerine that may fit. Maybe they will sell you a plug? Would at least get the driver functional.

I have a pair of 808 with no diaphragms I might be talked out of. Transitional model, they have the newer tapered body but still metal phase plug.