It has to be said that there is a real shortage of decent airgun shops in Kent. I know of one in Dover, though I've never used it myself, but it has'nt got a brilliant reputation. There are also shops in Hythe and West Malling. Tried to visit the one in Hythe once, but it was shut (and it's not very big.) Never been to West Malling, but I seem to recall they are a general 'Country and Tackle' type shop with a small airgun section. Chris Potter's in Tunbridge Wells is similar - they specialise in shotguns, but have a small air rifle section.
To give you an idea of the quality of the shops in Kent, I bought my FWB P70 from Dowlings, just off the M40 (Berkshire?), and my AA S400 was bought from BAR via the net. The only airgun I have bought in Kent is my AA Pro Sport, and that was from an ironmonger's in Sittingbourne who happen to have an airgun section. Strange as it may seem, I do believe in supporting local shops, but not many of them are able to offer what I'm often looking for.