Whilst I obviously don't condone buying from anywhere other than emagictricks.
http://www.emagictricks.co.uk/default.php?cPath=17_33
It would be fair to say that various magic shops specialise in different items, and in many cases some items may be available from one shop but not from another.
if you are anything like me when looking for a specific item you tend to search through all your favourite shops until you find what you are looking for.
There is a new website launching that proposes to do this searching for you - giving a list of all the stores that stock the item, and the relevant prices (including where possible postage).
This to me looks like a very good idea.
http://www.bargainmagic.co.uk/