Cylinder Head problems!

[AlFos <AlFos@domain.elided>]

One of my cylinder head gaskets has gone (combustion gasses compressing the
cooling system).  The top end is also a bit 'rattly' but I don't think it's
imminently terminal (don't think it's cam chains).  

I've been quoted by a garage which I believe to be reputable (Abinger Motors
near Dorking), and which specialises in Stags �1,000 - �1,500.  They inform me
that both gaskets will need to be done together, that it is very, very unusual
to remove a Stag head without it needing to be skimmed (machined), and that to
do this the heads will need to be stripped and then rebuilt.

It sure sounds like a lot of money to me but the car is used daily so I can't
afford to do it at my own leisure (if I could do it).  So what I really want
to know is does the above sound reasonable or am I being robbed?

                   Thanks in advance, Al.