https://www.cbo.gov/publication/53637
Link above is to the actual CBO report for those interested in reading it.
The money talk in the article is a little confusing but basically CBO estimates shipbuilding options as:
355 ship fleet = $103-104 billion per year shipbuilding budget from now through 2047. There are two different pathways described to getting there. One gets you there sooner but both cost about the same.
280 ship fleet = $91 billion per year shipbuilding budget from now through 2047. This is funding at current levels.
230 ship fleet = $82 billion per year shipbuilding budget from now through 2047. This is a reduction to historic funding levels for shipbuilding.
So, spend $12-13 billion more per year until 2047 ($360-390 billion net increase) and get to the 355 ship goal sometime between 2027 and 2037 OR spend the current amount per year and maintain the present 280 ship fleet OR spend $9 billion less per year ($270 billion net decrease) and shrink the fleet from 280 to 230 ships. The delta between the two extremes is $660 billion over 30 years, a tidy sum.
A quick scan of the document reveals the well known fact that the majority of the system lifecycle cost is in its operation and sustainment. Interestingly, the option to procure the vessels and place them into war reserve storage to save on these costs (until needed to meet contingency requirements) is not discussed at all.
Putting modern ships in WRS has actually proven to be a surprising money sink - modern electronics do not like to be left unused and there is also the issue of having to completely overhaul/update systems when pulling them out of reserve. Some countries have found it was actually cheaper overall to just run the ships and update them as they go along than to suddenly have to update everything after pulling the ship out of mothballs.