Here is a good advert for one - timber 1960. 1.4m draft. Sold for $19k but an excellent example obviously.
www.dbyboatsales.com.au/listing/daydream-28/www.dbyboatsales.com.au/?bdbrochure=daydream-28Would not expect your glass boat to be "different to other Daydreams" - just built in grp and not ply and timber. However this thread (going from 2006 to 2020) indicates the grp ones had higher topsides - guess you could confirm that from the photos of the timber ones compared to yours.
www.sailnet.com/threads/daydream-yacht-info.25645/5t is indicated here but that seems a lot for a 28fter so may not be accurate. But Cav28s have a displacement of 4.1t so it may well be right. Daydreams and Cav 28s are very different designs obviously. Daydream ballast mass is difficult to find. Very seaworthy boat designed by Ken Watts.
www.buyaboat.com.au/buyaboat/yachts-for-sale/used/sail-monohulls/daydream-28-classic-yacht/264432Other information you need might be in the adverts or in the 14yr long thread.
The Bluebird was Ken Watts first design, before the Daydream. Obviously both are Australian designed classics. I saw a Bluebird beat a well sailed Farr727 on scratch in a twilight race on the harbour in the early 80s in a black noreaster - obviously the Bluebird was also more than well sailed..............