You can program an eBay or aliexpress key (using an AK90 on the EWS module).

I have a couple of keys from the latter. I haven't tried programming them with my AK90 because one of my original keys still works. The other original one went through the washing machine around 2006 and the remote party no longer works. It still starts the car so I have one of the new keys programmed to do the remote functions and the original on the same keyring, as a combined working spare.

Check Google, YouTube or XO for more info on AK90.