I've never tried the Lancome brand of foundation, so I'm not exactly sure what color/finish it is. There are, however, a few drugstore foundations that I know and love, and maybe you could try your hand at matching yourself. Here's a lovely tutorial that's really helped me when picking a foundation from the drugstore~
(This channel also has such a great variety of helpful makeup tips)
I really recommend Revlon foundations. The Colorstay line is my favorite, along with Colorstay Whipped. Look up some opinions on the best drugstore foundations for heavy coverage, light coverage, etc.
Also, most American drugstores allow you to return or exchange a new foundation if it turns out being the wrong color. Ask the workers there about their return policy.
EDIT: I also use a website that PSY-chan mentioned, but it's called Findation. http://findation.com/
That may be your best bet ouo