I believe Mazda has a continuation part number for the FD sensor. Not cheap though.

But can you trust a 25 year old used one?

 

The “continuation” part number is a revised part that comes with a fitting kit. I bought one and tbh it’s a bit of a ball ache. You get a bracket to change it to a dual sensor, and a bunch of hoses. If you do end up ordering the new version from the heritage program, be aware that there are two slightly different versions for series 6 and 7/8 cars as the coil pack placement is different.

 

Since you brought it up:

This seems to be the only notice Mazda gave of the coil mounting position change. Upper is versions 1~3 (Series 6), Lower is versions 4~6 (Series 7~8)

This change caused a lot of grieve to unsuspecting mechanics.