To the best of my knowledge there are very few Big Time Dealers in your area. Unless someone knows better. However, M.G.Sharpe Models at 712 Attercliffe Road Sheffield has odd bits of LGB in usually. Also Rails of Sheffield 27/29 Chesterfield Road Sheffield have LGB usually second hand which they sometimes list on Ebay. Links included below.
http://www.mgsharp.com/
http://railsofsheffield.com/
Hope this helps.
JonD
http://www.mgsharp.com/
http://railsofsheffield.com/
Hope this helps.
JonD