What is the correct sheetmetal thickness for 240 18g, 20g and where to get in Melb

[aircobra]

Back from a break so back on this topic

Need to make a couple of patch panels , presumably 1 mm and 1.2 are the way to go?

When I measured up some of the parts, they seemed to be only0.7 to 0.8 though

Presumably these are the standard sizes in Oz

Cold Rolled Steel Sheet - Melsteel 

[C.A.R.]

Measure the thickness of the original panel, then replicate in the appropriate thickness steel.
0.7mm & 0.95mm cold-rolled are both available from steel merchants.