Looks ok to me - a few weeks ago a bike dealer in Cork was selling a tidy looking (and on the road) GB400, 23,000km for 1300 euros, around £1150 at todays rate! I'm still kicking myself that I didn't throw the Motolug in the back of the car and buy it despite a near 600 mile round trip. Long gone now unfortunately. That's the sort of money that a parts-only bike would go for as a decent set of GB wire wheels would fetch around £500.
Not sure if Tommy saw that one for sale on Donedeal?
Regards