JohannesTN: So I found this driver circuit which I guess would be appropriate: LED Current Driver
Yes, that would be the circuit I just gave you above - it happens to have a FET instead of a power transistor - the difference in this case is quite immaterial.
JohannesTN: Would a driver like this be appropriate if I choose to buy a driver instead of making my own? each led-pcb would have it's own?
Well, it might, but it depends on whether you mean "like" that or that one in particular, which is rated at 1.5 Amp whereas you specifically want 330 mA. And at $4 each for six of them assuming it could be re-adjusted to 330 mA, it would be rather more expensive than the circuit I gave you.
17V would be quite a reasonable voltage. However you can easily get 19V laptop power supplies rated at 3 or 4A (dirt cheap second hand too) which would work just fine in this application. If each current driver is dropping 4V at 330 mA, then the dissipation in the control transistor would be no more than 1.5W.