Sensational find. My first boss was a Nav on Canberra's with the Rhodesian Air Force, not sure if he was involved in this raid but these boys certainly sound like they did the business!
Have a recording of my mates Dad on a Canberra raid in Vietnam with the RAAF, makes good listening too but back in my home country unfortunately so can't put it up here. Will dig it out on my next trip back.
Good link here to the Rhodesian Air Force:
http://www.rhodesianforces.org/RhodesianAirForce.htm