PlayTech already have a lower than usual RRP on these, so they're quite cheap compared to other stores.
The 6-way model is sold out, but the other sizes are available.
8 x AC Power, 2 x USB - $47.20
4 x AC Power, 2 x USB - $28.00
$3.90 for shipping, or you could get Warehouse Stationery to do their 5% off price match