Hey westsider,

Welcome to repgeek. The UK is actually very "lazy" when it comes to customs, and thank God for that. There are usually no problems getting by customs but you have a couple of dealers that are UK based.
Have a look into Narikaa and PT on the collectors section.
You also have trusted asian dealers that are superb and very trustworthy. Andrew, Sead, Josh spring to mind but there are many others.
Have fun and let the reps flow...