Just been quoted £63. Does that seem about right to anyone?

£16 for the bearings plus an hour or so twatting the hub with a big hammer.

probably about right.

You can do them yourself for the price of the bearings, and I even think the instructions are on the Hope website…

You’ll need 4 of these & a big hammer
http://simplybearings.co.uk/shop/p6184/SKF60012RSHC3+Sealed+Ball+Brg+12x28x8mm/product_info.html

Instructions here
http://www.mountainbikerides.co.uk/fettling/hope_hub.htm

What wwaswas said.

Although they are standard industrial bearings, so you can get them from your local bearing supplier (Brammer/Eriks etc) for less than a tenner and fit them yourself.