This is a non-circulation issue denominated in the currency that has no purchasing power. If you read about Western Sahara
http://en.wikipedia.org/wiki/Western_Sahara , you'll see that Moroccan, Algerian and Mauritanian money are accepted in the territory.
Thus, the value of this piece is determined only by demand, that is if you find anybody wishing to pay for it.
A similar issue, also devoted to Zeppelin is listed in Krause with an estimate of $50, though I don't see any justification for such a high price.
I collect coins and tokens which circulated in Africa from 18th century to 2000. I sell about 7000 illustrated world coins from
http://www.avscoins.com.