Help?

Okay so I wanna get the HD Liquid foundation from Coastal Scents... however, because it's online I can only pick shades from what I see on my computer screen or from what people tell me, and also I can't really afford to make a mistake as they ship from the US so delivery is pretty expensive to the UK.

I was wondering if any of you guys have tried it, and know which shade would be right for me... unfortunately I don't know my MAC shade but with Revlon Colorstay I am Sand Beige.

Any help is much, much, much appreciated!
Natalieslovex