There are people making them (contact Davsgold - X coils) but you need to use either a GPZ14, GPZ19 or NF Z coil to remove the coil plug end with chip to make the adapter.
To buy one I'd assume you'd have to find a seller that still has an intact stock coil (or you are willing to provide one) & you'd be purchasing the X Coil, the adapter & the doctored GPZ coil (as it's now not usable without the adapter)?
Probably just cheaper & easier to find a used GPZ14/19 going cheap & have the adapter made if you don't want to try making one yourself.