Hello Neal,
You could drive over to Göteborg. There's a big maritime museum there with a destroyer, Swedish sub and even a monitor, like the ones used in the American civil war. There are other vessels you can go on board too.
From Göteborg you can take a ferry to Frederikshavn and drive through Jutland to Northern Germany. On the way, just off the motorway E45 is a city called Aalborg. There is also a maritime museum there with an old NATO sub and motor torpedo boat.
I don't know if the route is the most practical for you, but it's an option.
And whilst you are in Germany don't forget to stock up on beer, soft drinks and chocolate etc. I think it's a lot cheaper than in Sweden.
