just a grp A head gasket £65 and new bolts£25.

labour - well i can do it off and back together in 5 hrs.

so a specialist with all the correct jigs, hoists and tricks may be 4 hrs - but that doesnt include this below...

but you may need the head skimming£30, and a few other bits and bobs, like the o ring for the thermostat housing £1, the short pipe from the water pump to thermostat housing £5, a cam belt for good measure £30and if it hasnt been replaced, a new cam belt tensioner pulley£30.

new coolant and an oil/filter change afterwards would also bee good.
then you find that half teh exhaust studs are missing, that cam shaft caps have been overtightened and been stripped so need helicoiling and that the head has already been skimmed to death and there is no more life in it - welcome to cosworth land