Silver Cross carrycot - am desperate!

[ItsNiceItsDifferentItsUnusual]

I got the Silver Cross SURF for dc1, and am planning to use it for dc2, hopefully with the newborn carrycot attachment. They used to sell this separately, but it is now only available when you buy the entire pram system!

Does anyone know of any decent outlets where I might find one? I've tried the Silver Cross one, and am keeping an eye on eBay, but no luck.

My other thought is that Silver Cross sell adaptors for Britax and MaxiCosi car seats...anyone have any insight as to whether they would also work with those brand's carrycots? I've called Silver Cross but they wouldn't tell me.