Hey Serpentis, I'm not entirely sure of a very pale yellow-toned drugstore foundation but if you're willing to go online, you can definitely find some great foundations for drugstore or close to drugstore prices.
Graftobian Hi-Definition Creme Foundation is really nice for dry to combo skin and it comes in a ton of very light and very dark shades. They recently came out with 5 new shades for very fair skin with warm and neutral undertones.
Camera Ready Cosmetics is a trusted retailer and they sell Graftobian, along with a bunch of other theatrical makeup brands. Theatrical makeup can be a great option when you're looking for hard to find shades at good prices.
I hope I haven't failed you on your original question! =)