I'm using an '03 ECU in my '02. Research I did a couple of years ago when I bought a spare (for Ecutek flashing) indicated the following are OK for use in an '02:
AF411, 420, 422, 423 & 424
AJ030, 031, 040 & 041
I ran the '03 AJ030 in my '02 (factory part was AF422) for about a month with no problems before getting it flashed.