Reasonably easy to purchase, it just depends on how much you're willing to pay.
Postage from the UK should be about 75 quid plus whatever you pay for the beer engine. You can get a new EWLbeer engine for 99 quid or a second hand one off eBay for 40 quid if you're lucky. There is a source in Australia who is a distributer for an English mob who recondition them; IIRC NNL brewery services will do a recon unit for $450 AUD or so - best confirm this with them yourself. Plenty of options so price is the consideration. Heck if money was no object you could buy a brand new Angram beer engine from the UK.
Cheers Malted,
Yeah have looked at the UK route - convincing swmbo is another story. Price obviously is a factor. Will keep trauling ebay.