Looks like an awesome unit. I doubt that there is anything wrong with the current filter housing, most likely never had too many cycles through it.
But, since you are in Adelaide, go and see Rob from Dependable Distributors, they have been dealing with compressors for years and offer all sorts of useful advice and umpteen years ago became a Bauer distributor.
I bought an NOS Walter Kidd off him a few years back and found him to be very helpful, sold me a LF filter housing for much less than it was worth. They have all sorts of stuff out the back that is very useful to guys like us.
It took me a little while to get hold of Rob, he sold his business about 4 years ago and now works at B.L. Shipway. He unfortunately doesn't deal with anything scuba related anymore.