Did you create the designs that would be printed by Customink? And yes, you can take the printed tshirt, or even just a print out of the picture of your design and any screen printer should be able to reprint the shirt for you. However, if you don't have the original or high quality artwork file you will most likely be charged to have the artwork tweeked or recreated. Additionally, most screen printers have a minimum quantity of shirts they will print; they won't print just 1 unless they have a DTG machine or can use a heat transfer.