yer Super Cheap, Repco have all those boxes, you might find one that is close enough to the right size?
There a few places that sell things like that for work utes, but they all seem to buy them from the manufacturer and would charge you heaps for a custom size one.
I bought a undertray tool box from Tonga Metal (Toombul Rd), they make everything in the same shed that they sell from, no showroom, you just walk in to the factory kind of thing, but still expensive.
If you want something custom made, find a sheetmetal business, preferably in an industrial estate. Tell them excatly what you want and get them to ring back with a quote. You'll get the best price if you go straight to a factory/sheetmetal business, preferably one that doesn't have any kind of showroom, and the only office is a portable building in the car park.
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