Making your own BW or ID is definitely the way to go. Buy two decks of bikes, one red, one blue (seconds even - for the length of time anyone's going to see them, who's going to notice?!) and treat them yourself properly, I've had 100% success rate. Obviously the other plus is that if you want to use tallys, fourniers, masters etc. you can.
P.S. Do not pay more than about £5 for the "treatment"! I do object slightly to magic shops whacking a significant mark up on this when the principle is not (as far as I know) copyrighted to anyone. If anyone's unsure about what to buy, ask
