nothing jumped the shark in 2002
yes some new electronic features were added (stability control etc) but when you follow owner reports on the forums closely, you'll see that the pre 2002 models have more electronic component failures than the 2002 (and when you consider that only a few hundred pre 2002 463 series are on the road versus several thousand of the post 2002 463 series - the 2002 and later seem far more reliable).
Only OEM ring and pinion are available for any of the G series. No aftermarket R&P have ever been available.
You are looking at around $1,000 per set of R&P without bearings and labor
rear R&P
front R&P
and yes, you are right, that funny € sign means Euro - $ to € = 1.33:1
here are the 463 R&P gear sets:
463 R&P pdf
gear sets for the 460 series:
34:7 , 44:9, 37:7 and 37:6