I believe you can buy one at invoice these days.
Or another option (if you like to save some money), you can still pick up brand new 08 Convertibles for around 15,000 under MSRP. Most of 08 sedans/coupes are gone but I do see a lot of brand new 08 E93 M3 convertibles out there.
X5M: Dinan Exhaust | Dinan Suspension | Velos Tune | BMW Perfomance Splitter | Lux V4 | Euro Mirrors | H&R 12/25 mm Spacers | IND Cosmetic Package
PAST: 08 E90 M3 | 08 E92 335i | 03.5 E46 M3 | 99 E36 M3