We got our cat from Wood Green and were told she was approx. 4 years old, which would make her about 7 now. But she seems much older... I know with horses you can look at their teeth to estimate age, but is there any way of telling with cats?
Ask the vet next time you're there for a check-up. Although a vet did say to me that if they're very young or very old it's usually easy to estimate an age but if they're in the middle (2-10ish I think) they are hard to age. Then again when I got my old boy the vet said 8-10 and the current estimate for him 8 years later is 18 so they are quite accurate!