As for accessories you will find New Look to be full of Maritime inspired jewellery at rock bottom prices, so copying the look needn't cost a fortune. A piece of thick rope will work as a belt or as handles for a bag.
Loungefly Canvas bag - Urban Outfitters - £38
Designers are still loving it too as the trend was represented in the catwalk shows of Chanel, Jean Paul Gaultier and Tommy Hilfiger. There even seems to be a bit of Pirate thrown in, but my suggestion is to leave that to the most daring (and fancy dress parties).