Nice to find a Galaxy appreciation page and read Galaxy tales like Olly's above. You can see why they have such a following, and a mystery to the old ones after Dawes' records are lost.
This is mine, bought for £77 on Ebay a couple of years ago (I've only fitted the saddle and pedals) and I'm not sure exactly how old it could be.
It took me and 15kg luggage 1700 miles in the winter to Morocco without a single hiccup.

Looking at other's research, it could be a 1977 Galaxy GT, though those gold stripes on the seat tube suggest it could be older (like wahoonc's brown one above).
The serial is AC2831