I am Premium BF3 both on PS3 and PC now :)
Well on PS3, I dont think you can purchase them Via credit card, because it all depends on which region is your account.
1st: If its Lebanese, then there isnt any online gaming with that account (as far as i know)
2nd: If its any other account, you cannot use your credit card on them.
So your only choice is to buy PSN cards.
They are available
@PcandParts for both US and UK accounts only.
And you wont find them elsewhere in Lebanon other than them,