Easy to do. HEH!!!
Pick a piece of wood a little longer and wider than that model at the local Home Depot etc,. Like a two foot long by 4 inch wide piece of oak. Cost maybe five bucks.
Hint: if this ship thing kicks in, it might be the time to get five or so of these cut.
Now I found a sign shop (spoiler: the foreman there is my best friend), but you get the idea. Show up with your five planks and ask him/ her to put a routed edge all around the top. Maybe they charge you ten bucks total. Or not, square edges are ok too.
Here's the hard part. But not really. If your wood base is a 1x4, it is really 3/4" thick. Your ship model is a big one, which I like to display low and squat on the wood base. Frankly a battleship on two stands is kind of minimal, but Bismark is a small battleship and I would do that.
CAREFULLY drill two holes into the keel. This is where disaster will strike. If you do anything too fast too big: you will split the hull.
I would start with a 1/16" drill, and at least three or four more until you get a good hole.
Where are these holes? That is the big question, the one that separates you from the rest. All on account of your eye. Over time I have found that on a battleship; under center of the turrets closest to the midship structure looks good.
Go to the afore mentioned Home Depot and buy some pan head 10/32 screws at least 1 1/4" long. And nuts.
Make the two holes in the bottom of the ship big enough (1/8") for the screws. Then carve a big pear shaped hole off to one side each for the head of the screw to fit up and in to.
Buy a piece of 1/2" brass tube. Cut two sections each about 1/2" long, polish them up with toothpaste.
Drill a pair of holes into your piece of oak.
Fit the screws up into the hull, slide the tubes on, drop the screws down through the holes you've drilled in the oak, and tighten the nuts.
Put 4 of those little vinyl feet they sell at Ace on the corners and you are all set.
Forgot- stain the wood and put a semi gloss finish on it.