It would not be the same 76 cm, because a satellite in orbit is in free fall. So the mercury in the barometer will behave as if it is weightless. All the weight of the mercury is essentially "used up" in maintaining centripetal acceleration in the circular orbit. If, as usual, the tubing above the mercury is initially under vacuum, the mercury will be driven by the outside pressure all the way to the full length of the tubing, which is greater than 76 cm.
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If the pressure inside is maintained to standard 1 atm by means of suppose a heavy gas, then it would mean that when the satellite revolves the entire satellite system is under free fall, all the gas atoms ,the barometer tube ,the mercury in it ,all are under free fall . Thus in such a situation the gas atoms won't produce any pressure and if there is no pressure to be balanced then I think that the mercury in the tube won't rise.