Yep. I had the same shock back in April 2002. Gawd I feel old....
Factory prices at the time were $500/wheel (17") or $250/wheel (15"). And for the record the 15" wheels weigh about 15kg, 17" about 19kg - 4kg diff PER WHEEL! (including tyre BTW).
Also found that replacement parts (the clear repeaters are a standard Cooper S part) are cheap as (I'm often seeing prices up to 25% cheaper than my partner's Barina), but optional stuff (wheels,
JCW stuff etc) is expensive. Didn't stop me spending $350 on a pair of
JCW mats tho!