I do not have a lot of success expanding my Spanish Morocco revenue stamp collection. They are seldom for sale.
However the next best thing is collecting revenue stamps overprinted and or surcharged for postal use.
TANGIER, although Tangier was not part of Spanish Morocco, it was located inside the Spanish Protectorate.
Spanish Morocco revenues overprinted for postal use
Spanish revenues overprinted for use in Spanish Morocco, postal giro and telegraph use
When I buy stamps on eBay
I will always look at the other items the seller use in order to try to minimize shipping costs.. Below is a Pro-tuberculosos set of 1953, nothing to do with what I collect, but looks very interesting