Sorry for the delay.
I don't think that the band had a name but I will ask my Uncle who is the only one still alive.
Their surnames were BLACK and they were all of the same family. I recall them playing at the UFS Hall in Atherton Road at one time and they were a dance band primarily. I was only 3 in 1950 and grew up in Oakleigh but I remember this quite vividly.
My grandmother ran a men's boarding house in Atherton Road and that is where they had their practice sessions.
The band was still playing about three years later when a school dance was held in Notting Hill for my primary school there. It probably wasn't Johnny Ray but an impersonator who performed that night as well. He was definitely introduced as Johnny Ray though.