If you wana stab at it yourself, you could take a pic of the side of your boat, drag the image into adobe illustrator free trial version, use pen tool on new layer to trace a template outline, then make a graphic on a new layer and either layer mask it or manually trim it to fit. Then measure the boat back to front where the graphic would sit and just scale the design in illustrator while holding shift to maintain proportions and match the dimension measured. Save the file and mail it off to someone thats able to print it up.
In the end its all trial and error tho to get it right unless u actually send your boat to have it done by someone and even then itll probably take them a couple tries to get it right.
But if it makes u feel better, i love the look of that boat. I say keep it as is