'Citadel/Room 415' is indeed one to get, if you can find the vinyl. As is Metropolis also on RCA. There was a twofer UK LP issue of these from 1979 that is worth looking out for. There is a recent CD issue of 'Metropolis' but there was concern about the sound quality (not a problem on the original vinyl issue). Not sure whether or not 'Citadel' has come out on CD. If not, it should be.
Is the Dave MacRae on these sessions (and on countless others from the 70s, especially on UK jazz radio broadcasts) the same Dave MacRae who was on the Don Ellis albums for Pacific Jazz? I believe he is a New Zealander..