Do normal NHS practices have different sized speculum's for Cervical Smears!

When I was a lad all hospital clinics and GP practices used metal speculae which were sterilised and most had some virgin speculae (yes that is the real name,) that were rarely used, and also some large and extra large which even then saw a fair bit of service. These days they have been pretty much completely replaced by plastic disposables with most practices only carrying the standard medium size.

You do not give your age, smears are started at 25 in England and Wales and 20 in Scotland. Before those ages it is rare to need to do a speculum exam. Personally I would be loathe to use one on a virgin without a clear cut indication.

GP for more years than I care to remember

Yes they do. The last time I went for a test the nurse told me that there were different sizes depending on if you had children or not.

Yes they do. If you're a virgin you really dont need to go for a smear test.