Key recoding in a classic
 

Hi I only have one original key for my 99 Sport.

I got another subaru key via ebay which I had cut, but although it came with a supposed transponder chip the delears couldn't code the key. Think the transponder bit in the key might be faulty.

Question is how does the recoding process work.
Could I get a transponder chip from a known genuine subaru key say from a writeoff then fit that to the replacement spare key, and get the original and new key recoded?

Dealer might know, I've put one from my old, worn out key into my newly recut key.
Trouble with recut keys is they are very "sharp". The one I've got opens driver's and passenger doors and the ignition, but won't touch the boot:(