Could be a variation of one of these. Personally, I don't like this style of pith helmet (on the web page) and would go for a more 'Pickelhuabe' form if possible, had I been in the Imperial Marines. Perhaps this is similar. Interesting helmet.
The Germans had so many sun/pith helmet variations that it is hard to keep track. It looks similar to some of the helmets used during the Kaiser's trip to Palestine in 1898, but similar helmets were used in Morocco in 1905.