[erik_seaberg]

Could have used a ship; that's how they delivered the larger Saturn V stages from New Orleans and Seal Beach to Cape Kennedy.

[Rebelgecko]

Would not be practical for a Vandenberg launch (which was a shuttle requirement that was never taken advantage of)

[0xffff2]

To clarify, there are many places where the boosters could have been manufactured and transported by ship. The shuttle SRB's where manufactured in Utah, where transportation by ship is impractical.