That seems a bit steep for just a head gasket, but who knows,(maybe Steve B. or Donnie D.)BTW, with that rate of oil consumption, are you sure it's the head gasket??Any signs of increased pressure in the crankcase, ie, oil in the air cleaner or the front cover leaking. make sure it's not one of these before you jump into tearing the head off. That's pretty hefty oil loss.
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.