Wants To License Art for T-Shirt

Dear Rich: My sister and I have a start up apparel company (LLC). We are paying a graphic artist a flat fee to use a piece of his art to print on a t-shirt. The art piece will only be used for one release/collection and we agreed on a flat fee as we don't know if any of these tees will sell or how many we will end up printing. Is there a basic contract for this type of arrangement? There's a long form and short form T-shirt license in our book, Getting Permission. You can also download the short form agreement here.