The
SEAWARSTORE has
a series of shirts for naval geeks like me.
Famous Nineteenth Century Naval Battle Tee-ShirtsDreadnought Age Sea Battles Tee ShirtsAnd many more! Great White Fleet, Sink the Bismarck, Midway, etc. There are many history geek tshirts out there, but very few on naval subjects, and even fewer on 19th century and dreadnought era battles and themes.
There are also polo shirts with embroidered naval flags of the time period:
The SEAWARSTORE's Naval Theme and Naval Battle Shirt page is
HERE.