1. Try Loyalhanna Dockyard , if they don't have the decals,look for Woodland Scenics dry transfers in the railroad section of the local hobby shop. You can apply the dry transfers to blank waterdlide decal paper, and the apply the homemeade decals to the model.
2. Look for 1/72 scale armor figures, specifically US infantry or Marines from WWII. You'll probably have to shave off some parts, like gun belt and back packs.
3. There aren't many color pictures of PT boats, try looking at Knights of the Sea.