Stumped at the fabric store

I had a great idea for my 5yo daughter's Christmas dress... but I don't have the fabric I wanted in my stash - so this morning when I was without kids, I went to 2 local fabric stores. And I was sadly disappointed. I want some red plaid (poly-blend), but I only found very muted colours (greys, browns, beiges) or very dark (Black Watch Tartan). Now what do I do? I wanted to make this dress this weekend!