The sole preserved type VIIC U-boat from WW2 faced the same problem when the Norwegian navy surplussed it. Despite petitions from the U-boat crewmens’ association to purchase it as a war memorial, the West German government was unwilling to do it.
The U-boat association’s members raised their own money and bought it themselves.
Yeah, I believe there’s a USS submarine at the Texas site as well. Lot easier to hoist a submarine boat out of the water than it is to do with a battlewagon. Lot of heartbreak after WWII when the military had to surplus tens of thousands of historic vessels because in the end, there’s no way to pay for them. Course those were the days you could get a tank shipped to you in a kit. Saw it in the back of a magazine.