Id bring a rag. Id also bring a new chain and two quick links, and id bring the extra links i cut off when i sized it.
The chain goes on the bike. The links go in with the patch kit.
The rag is for wiping off the excess machine oil that id use to lube my chain.
Maintenance aboard ship ought to have barrels of oil.
Oh, and a q tip to apply it would be handy, as well as a thimble-sized container. Two thimbles-full usually does my chain for a month.