I don't know if you've tried the local supermarket but peppermint extract is supremely hard to find. They don't even seem to stock the fake stuff so finding proper Peppermint extract for such a reasonable price made me a happy camper.
You only really need to use 2 drops or so which makes this extract in particular very good value.
It's a good addition to any cupboard. Read more
I would recommend this product to a friend.