I have a 97 without any remote entry/alarm, just a basic key with a tiny light in. I can't find any part number on the keys, but they both look exactly like 94453804100 from a google.
I also found this, which has a pic of a 'spare' type key with a different 986 code...
Boxster Extra Keys - Pelican Parts Technical BBS (edit, actually looks like thats a remote one?)