How did you come to that assumption
It was an assumption having seen the same question asked here many times before. Intuition perhaps? Anyway, I did however write "if this is the case" which offered the chance to reply
Anyway, turns out this is what Samstorey was looking for and now that we know, I suppose that it depends on the quantity that you're looking to buy. Most, but not all producers of decks want a pretty sizeable order.
If it's gaffs that you're after then obviously the Ellusionist decks are the ones that spring to mind but there is also the CAJ deck which is well worth considering. For other specialised cards I would highly recommend cardmaker.
http://www.magicbycardmaker.com/pageID_2850155.html
It's a VERY expensive way of producing business cards and instead, why not use your old cards with a printed label stuck across the face/back?
Member of the Magic Circle & The 2009 British Isles Close-Up Magician of the Year
It's not really an optical illusion - it just looks like one!