Where to buy mouse tray/mouse pad holder?

[q_hada]

I'm looking for a mouse tray/mouse pad holder (one that clamps/screws into your desk, and optimally rotates, tilts, and is height adjustable) in Toronto. Does anyone know where to get one? I tried Staples, but they only had keyboard + mouse trays... I don't need a keyboard tray, so that didn't help. I'm not sure where else to look. Online stores would be fine too (I already checked ebay).

Thanks!