The real question is whether they're asking for fresh or dried.
For fresh red, you're probably limited to Fresno (pretty mild), ripe jalapeno (rare, but the places that carry them they seem to be less likely to be duds than most green jalas), Thai long (a good choice), Thai bird's eye (very hot but too small to add much flavor) and some variant on habanero/scotch bonnet (possibly too hot).
If it's dry, you'll have better chances finding something, I'd aim at guajillo (more flesh and flavor) or arbol (more heat).
What is patriotism, but the love of good things we ate in our childhood?
-- Lin Yutang