Suzy,
Can I suggest that you contact a member of the HRSA (Historical Radio Society of Australia) at their website
www.hrsa.asn.au
They will be able to put you in touch with someone in your area that will have the required equipment and knowledge to play your 78rpm recording for you and may even be able to transfer the contents to a modern format so you can then play it yourself on computer etc.
I am sure they will be very helpful and sympathetic to your needs.
I hope it all goes well.
Best regards,
Mike Barker.
BVWS Auctions.
British Vintage Wireless Society.