In 1930 a font was something made of metal (or wood) and intended for putting ink on paper. Any large lettering on an irregular surface (like a boat) would have been hand-painted.
Try searching for Dutch signs from that period (shops, bars, restaurants, hotels, etc.) and you'll probably find the sort of lettering you would have seen on boats.

Thanks for the advice it might be a good idea to track down some images of signs billboards etc.
Thought it was a long shot at best since the 1930 is real old for PC fonts :)
I hope i can find a font that looks from that period although i doubt it.

If you had photos of type on boats from the period we might be able to suggest something similar.

- Mike Yanega

Took a picture of the lettering of the ARM-17, something like this i hope to find.
http://darkdesign.eu/images/projects/IMG_0177.jpg

This may seem like a strange choice, but have a look at Nick Curtis's Gandy Dancer. It has a handmade feel and some similar features to your lettering. It's also based on old lettering from early 1910-era.

- Mike Yanega