I don't know about your fixture, have you tried googling it in Aus, then contacting them. I have lovely American leadlight set of lights, wired for Aus, I bought them in Drummoyne, Sydney.

When I started doing reno's, that was one of the first things I wanted to replace but the cheapest quote I could find was a touch under $3000 and that was from some random guy from Gumtree that I could barely understand. Everyone else looked upwards of $4000 and that's just for installing the new gyprock ceiling. I had plenty of other things that I needed to do the place, so I quickly ruled that one out. But now after living there, I don't even see the vermiculite anymore. I'll just try and work around it. My thoughts now are to... 1) Remove the ceiling fan. Get a pendant light (either 2, 3 or 4 from my very first photo). Keep the bar light. 2) Replace the existing fan with something more modern. Replace the oyster light with an understated ceiling mount fixture, or just keep the oyster.

first store the dead animals the out of sight and consider Antique USA (white with a grey base) for all the painted walls, plain ceiling white for the plaster ceilings, white semi gloss for all the painted architraves and skirting boards and keep the timber ceilings and timber doors but replace the floral door knobs with plain satin chrome and use simple flat white and satin chrome ceiling fixtures in all the low ceilings and simple pendants in the high ceilings (good variety of both available in major hardware stores) and it would be worthwhile to replace the patterned row of tiles with plain white ( a textured white tile if you can't match the colour) and clean the blockwork walls and the floors look good

Your could install an offset pendant. Draping the wiring over a fixture in ceiling to make the pendant central.