Hi Colin,
I was going to make one up for my fusilier but historical correctness got in the way.
I planned, depending on your scale, to use wooden skewers (cocktail sticks for smaller scales).
Drill holes in to a piece of wood to form a rough circle to hold the skewers upright(ish). A little out of square will ad to the realism.
Then I thought to use varying thicknesses of plumbers hemp or sisal string woven through the up rights. The effect being more rustic than just using wire.
Then you can fill it with whatever putty you have. This will hold it all together, then with good luck and a fair wind you should be able to lift it out of your block and paint it up.
As I did not get too far with it you could be the designated test pilot.
Good Luck Mate.
Cheers,
Keith