He needs to contact his MAP. Usually the answer would be no - you are not supposed to charge the card until the item is shipped. But you can do a pre-auth, although that usually only lasts a few days, depending on the issuing bank
There is nothing to prevent a deposit being taken if the customer agrees. If the customer does not agree in a case where the goods are being obtained or made specially for him then you can decline the order, and indeed would probably be wise to do so.
Yes, our merchant account allows us to take deposits or down payments on certain kinds of orders. The only orders I do this on are those where the item or items are not in stock ready to ship or when the item is custom made for a particular customer. I ask for half down and the balance before shipping and have never had a problem.