Several guides I have show 7-9 hrs. The heavy end of that might be in house labor for valve grinding etc. Most shops in this area will likely bill for the prev. hours.
Most machine shops locally will hit you for $350 to deck the head, pressure test and magnaflux, grind the valves and do stem seals and guides as necessary (parts extra).
If the valve seat inserts or integrated seats in the head are cracked that number would go up substantially.
I like to clean the head and block by hand with 3m pads and laccuer thinner vs. the air "die grinder" with 3m red pad etc. Its easy to not keep hand held air tools flat causing high and low spots, particularly on the block deck.
You will also need a cherry picker/engine lift to lift the head off and to re-install it. Its heavy, 115 lbs, if I remember correctly
Good luck.
Andy