....Though they are getting fewer, after losing a couple of them this year.....
You definitely want to pay a visit to GRS, especially as it's so close to you. They are NOT the cheapest, by a long way, BUT they are probably the best stocked, and a good poke around there is always fascinating, Usually a good selection of second-hand stuff, including a lot of bundles of used track. Allow a good couple of hours at least for a thorough look round, ideally without someone nagging you to hurry up......
You're fortunate to be so near to them, though your wallet and cards may not agree afterwards.....
Jon.