BMW GB have got 3 in stock £702.13 + VAT This is exchange so will need your old rack. If you can travel to Oxford i could offer you a 10% discount off this price (£742 inc VAT) part number 32.13.1.095.577 (unless youve got an M roadster which are different)
Just try ringing round more scrappies - i found a couple that had them - worth ringing around though 'cos the prices varied a lot between breakers!! One wanted over £200 - but i only paid £110 for mine!!
Might not be able to use it on my car now so it may be for sale soon!!