as far as I know the ballasts needed to run the Phillips cmh are just regular mag core 400w hps.. no need to order those from the states..
These particular (Elite Agro) bulbs need a pulse start ballast, not all ballasts will fire them. Welthink makes a 315w for these but haven't found a supplier up here for them.
Here's the link... If buying a separate ballast and bare bulb
advancedtech is hard to beat though @ $200.00 USD for a ballast/bulb combo if you're running 220/240v, add another $50-$60 for a 120v down converter.