You can apply a sea theme beautifully with variety of knobs and bath decorative hooks available in this respect. ship styled cabinet hardware
should be a sure shot addition while planning to apply sea theme. They come in various shapes for example you can shop for seashell style knobs, Oceana Designer Knobs.. They are comparatively much cheaper  then if one buys them direct from the stores.

Other nautical or Coastal Decor like are Palm home furnishing stuff like art poster, anchor hooks, crafts and quotes.