If my long term memory is still working properly when I arrived at Miri in 1981 The Tranquilli**er Bar was located in the bottom Co-Pilot's House. However after a certain F/O (not me) left the beer cans in the freezer too long (none survived to be drinkable) for a Pilot's or Flight Safety Meeting it fell out of favour, and we then frequented one of the bachelor status Fixed-Wing pilot's house instead.
When Thridle Op Des moved up the hill to the Top House he brought The Tranquilli**er Bar with him as he owned it by then (departing Co-Pilots would sell their motorbikes, TV's, etc. on to new arrivals). The Top House was the better venue as it had a large walled open flat roof for the sundowners & curry nights.
Here is a censored photo of The Tranquilli**er Bar in 1982 at the Top House.