The water ban is for carry on, not checked luggage.
But, isn't your luggage heavy enough without all that added weight.
I can vouch for an easy transaction with Staples, I ordered the water and they sent it to the resort. It was there waiting for us upon check in. We left the few bottles we didn't use behind. Hopefully mousekeeping took them (or just tossed them out?).
You don't pay for shipping if you join Staples online first. Be sure to add your Staples number to your order. I actually called the toll free number to be sure all was okay with my order. The rep then changed up the deliver too address to show it was a vacation visit and not our home.
As a matter of fact, I have actually gotten into the habit of ordering water for our home now about once a month. It is easier on me having to lug it from the truck into the house, shipping is still free and the bottle price is comparable to the stores.
Good Luck!