Compression test results - skim head?

Hi all

I have been given the lovely task of fixing the 1999 A6 Avant Quattro 2.8 petrol that my SO blew up by allowing to overheat.

It needs the following doing to it:

New water pump (the cause of the original leak and overheat)
New timing belt while I'm in there
2x new cat converter section pipes as leaking and blowing from downpipe joint

(Total parts is looking like £700, which is a bit daft on a £1500 car...)

However before I do all this I decided to get it up to temp and test compression. Offside bank are all 145psi at idle
Nearside rear is 145psi, the front two are 100psi.

Questions:

Would this indicate a cylinder head gasket issue? (i.e. are they known to leak between bores, as there is nothing in the coolant or oil)

Is it worth my while doing just the other work or am I best off skimming the head too whilst I'm in there? If so how much is a head gasket?

Any thoughts on good parts suppliers for timing belt kit, and water pump?

Or am I best off scrapping it and cutting my losses? Its got 150k miles.

Cheers in advance!

If it has been overheated it says to me that the rings have gone so it’s pistons out whilst the heads are off which also means subframe out.

Oops wrong year forum, I'll repost in 1997-2004