I'd ask for the bill from customs if I was you just to make sure it is legit. Would not surprise me if they cancel the charge, shipping agents around the world add on dodgy charges.
Thanks. I haven't had the time to do anything about it but they sent me 4 or 5 sheets of paper...I believe a couple of those were scanned images of the customs bill.
I'll give them a call tomorrow either way. The truth is, I bought 3 monitors for $307 each and I would have been perfectly happy paying $327 each upfront...it's just annoying getting an unexpected bill 2 months later.