What would be really impressive is if you had a set (maybe, oh, 153 of them) which were 9x17 with one point on each one filled in. Then, pick which ones you need and randomly layer them one on the other. You might hit some (silly) maximum in terms of the number of layers you can have, but it shouldn't be that bad. (In addition, you wouldn't have to stick to 1-dot pictures ... you could theoretically find all the dots you need and randomly break them down into a set of blanks, each with 1 or more dots filled in.)