The comment about Suzo is not totally accurate, I have found they are Gimps even when you DO want to order in bulk.
I recently thrust an order in front of their MD (at the ATEI show in London) for 50 trackballs. I stated on the order that my price I would pay would be the same as the retail price Wico charge for the Suzo trackballs on their website ($24.99).
The MD at first denied any knowledge of Wico, and then said that they could not possibly be selling them for that price and the website must be wrong.
So they never got the order. They are really not interested in selling anything it seems.
Happ are fine but they can afford to be at their prices... Happ started in the UK and Frank Happ, who has been around for ever, is English before he moved to the US and started to expand (I mean he himself as well as his company!).