When I changed my name at my surgery in May, I got a new card pretty quickly (but, despite saying I'd got married, which was the point of the name change, I was still put down as a 'Miss'!?). Odd.
DH says the only time he's used his card in his entire life is when he's moved and re-registered, at a new surgery. I'd assume you'd need the number at least, so it'll be easy to find you in the system (?) , but you should be able to get that from your surgery??