Its a PITA...
I know NFU will give you a green card, and i know other people who have managed to get one from their company too. There are different views on weather its better to have a green card OR insurance provided by a 3rd party in country. there are pro's and cons.
Basically, you have to accept now that the cover you will get will be limited. I would almost say, drive like your un-insured and remember this each time you drive. You can get insurance at the border, i told them i didnt have a green card but the office was closed. they just waved me through and told me to sort it out at the next town.
Where are you sailing to? I know fineq (sp) south of Ceuta has insurance plasses. we had to pass through and camped at Martil because we made the crossing late (4.30pm). We got insurance from the only place in Tetuoan, which is opposite Cinema Espanol. Drive into town and ask for this place, its the only place there. think it cost us £75 for 4 weeks. dont ask me the cover because i dont know. my french is ****e. but it was a piece of paper to show officials when the **** hits the viscous fan. We know people who passed through Maroc without insurance, its your call.
G
