The trimmer who made mine is now out of business. I don't know of any trimmers that have made them before in Brisbane.
As you probably already know, there are two types of rear section. Late Mokes like yours and mine have the canopy out at/near the edge of the rear arches while earlier ones had the angle piece on the arch further in at the inside edge. Make sure you get the right shape. I think the ones on Ebay say they fit all with just a few adjustments. That's bull I reckon because the back part would be dodgy.
If I was getting a new one I'd get it made to suit zip-up doors because the lift-the-dot type doors blow goats.
Unfortunately I reckon you've got little chance of not having to leave the car with them.
Get on the Moke forum and ask there.
www.moke.com.au
M