You use InDesign or Illustrator and things like variables to increment numbers. Doesn't matter in your case, though. If you really are going to print it with an online service, you will just create a PDF with 300 separate pages/ artboards and could just as well hack in the numbers manualyl or use something liek automatic page numbering to increment them.
In addition, we offer a heat sensitive security paper. This is also heavy weight card stock with matte finish, plus some extras for our customers who take a serious stance against ticket fraud. The message, "Security Paper, Do Not Duplicate," is printed at a 45 degree angle, in a very light green, heat-sensitive ink. A slight rise in temperate, such as that generated by rubbing, blowing, or holding the ticket next to a light bulb or other heat source, turns the ink from light green to light yellow. Your ticket takers can tell immediately whether the ticket is valid or not! Once the paper cools down again, the message returns to its original color.