I was looking for a hard shelled case yesterday for my two new Godox AD600BMs and someone suggested the Craftright large storage case available at Bunnings Warehouse. The case is 515 x 435 x 225mm and is quite heavy even without the hardware inside. It feels sturdy and should hold its shape when stacked on top of other cases.
These are hard shelled plastic cases with foam padding on the inside. They come in at A$72 and are actually quite sturdy and heavy. They are obviously not indestructable like the Pelican storage cases but should suffice for general transportation and storage. The foam inside is softer than I expected which means I'll need to leave a lot of space around the edges.
The large case comfortably fits one AD600BM monoboc, plus the battery and the bulb. You'll need to cut through two sheets of foam for the monobloc to fit. The recharger could probably fit as well but I generally don't take them with me. I can also store them in cheaper shelving/storage containers.
A few friends have suggested replacing the stock foam with something sturdier from Clark Rubber or Pelican. The stores can also laser cut the foam to match my specifications.
The Bunnings i went to had a lot of stock but it was a struggle to find it in the warehouse. It's typically located in the handy tools storage section. Don't bother asking the staff because they'll be as clueless as the customer.
There is another brand of safe storage cases in stock but its slightly more expensive.
I'm going to attempt cutting the foam on the weekend with a stanley knife and a heat gun to get the lights into the case. Eventually i will have to chuck out the stock cardboard boxes as they take up too much space.