Here from NGC are the prices for this type of coin by condition.
https://www.ngccoin.com/price-guide/world/morocco-1-2-dirham-c-175.1-1283-1288-cuid-1201825-duid-1439078
Personally I would grade your coin approximately VF, considering that the edges are always flattened on this type. An expert familiar with this type of coin might grade it differently, perhaps a bit higher.
NGC doesn't price the 1286, as you mention only saying "rare"
Clearly this indicates it is more valuable than the other years listed.
As a first guess, since the other years range from $40-200 in VF, I might estimate the book value for this one something around $300, but this could be off in either direction. And of course actual sales often occur below book value.
I guess for a better idea of value you will have to hunt around for one being sold at auction.