I got mine at the local hardware store, I think the clerk said it was the same style as some Toyota's. Just told him no chip, just a metal door key, and he knew exactly what I meant (it happens to be an ilco P1114 B110). 5 min. and a few bucks later and I was on my way. The grip of the key is fairly large, but it fits my wallet fine. One could always cut it down if they felt it was too big.
Like I've said before I'm sure this is overkill, and I hope I never have to use it, but for a few bucks it's cheap insurance.