I agree with Jim. As you worded it it came out as replacing a head gasket and if that is all it is then that is an atrocious amount to pay. You can DIY as it's an easy job. Even if you pull it and take it to a machine shop for valve job it shouldn't cost over $700 total. But I guess $400 labor is about right if you hire it done.

1953 Chevy 5-window 3100
In the Stovebolt Gallery
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Dave
Engine & Driveline Moderator

If you can't make seventy by an easy road, don't go. ~~ Mark Twain