Most any paper supplier can get you cups. Normally cups have a 50 case minimum but that does not mean you have to buy the whole lot at once and store them. Depending upon your volume, or expected volume, you can pay as you go and your supplier will stock them. The whole process and cost is completely negotiable and greatly influenced by your volume. If you only have one shop and are low volume, you will not have much leverage but that does not mean you will have to pay up front and store the whole lot. Maybe you can pay 50% up front and they will store for 12 months??? Maybe 8 months and a monthly payment??? If your current supplier is not willing to work with you shop around. Present another supplier with the deal that you will move all of your existing business with them if they carry your logo cup.