Hello, I have searched everywhere for information on a bottle of Vintage Port I have gained in my possession and I can not find ANYTHING about it ANYWHERE.
This is what is written on the label please help and tell me what this is worth.

SWAN BARRACKS SERGEANTS MESS
Vintage Port
Commemorating
H.R.H Queen Elizabeth 1
On her Birthday in our Bicentennial Year
21, April, 1988
Australian Army

Specially Selected
1976 Vintage Port
BOTTLED BY THE MAKERS
THOMAS HARDY & SONS PTY LTD
REYNELL ROAD, REYNELLA, SOUTH AUSTRALIA
18% BY VOLUME ALCOHOL
750ml WINE MADE IN AUSTRALIA

This is Hardy's Vintage "port" from Australia, not Portugal as you'd expect.
That being the case it's most likely to be a fortified Shiraz, predominantly, with a touch of other grapes.
While I haven't had this particular wine, I have tried other makers from this vintage and they are drinking well.