Lunahippo, I dived with Kabaira dive a few years ago, Stephen Woolcott and his wife Marsha run the business. Kabirra dive is on the other side of the peninsulla from Rabaul but you can still see the active volacano plumes from just about anywhere. Very basic accomodation but we were advised Stephen is adding more facilities. Food was OK they have staff to do the cooking, basic but I found nice. The resort is not near any town and is very quite ( not in a built up area). Steven picks you up at the airport in Kokopo and after a very bumpy ride over the hill etc you get to Kaibaria resort. Extremely scenic place PNG . You can visit the volcano day or night, we did both, standing there in pitch black you can hear the roar of the volcano and see the glow from its crater, which is unforgetable and awesome, dive on reefs, Jap Zero, an obliterated Jap water tanker , Georges wreck near Rabaul Harbour, viz not great on the Rabaul side but OK , this is due to the continuous stream of ash belching out of the active volcano. Nice sight seeing opportunity, WW2 bunkers , guns, submarine caves, just out front of the caves is a 300mtr drop off. On the Kabiara side water is clearer as they do not get the ash drifting over them generally.
Diving was good Stephen has been there for years and new all the good spots for the day. Serach for Kabiara Dive Rabaul : what you see on theoir web site is what you get.
Cheers
Fishfngr