I am assuming that the location of this photo is Ipswich. From left to right we see Eastern Counties LC546 [VVF546] a 1957 Bristol SC4LK with ECW B35F body ; Eastern National 2506 [1651F], a 1958 Bristol LD5G with ECW H33/27R body ; Eastern Counties LK294 [LNG294] which was new in 1950 and is a Bristol KS5G with ECW L27/28R body

At Lowestoft Corporation Depot on Rotterdam Road is Leyland Titan PD2A/30 / East Lancashire H34/28R number 8 [BRT668C] which dates from 1965

Thanks to those who have sent me info on this photo. It seems that it is an ex Luton Corporation Bristol RE 373 (PXE113G), the photo being taken at their depot after the take over by United Counties

At the former Luton Corporation depot is a view of a Dennis Loline / Neepseed 842 (FXD182C) and an Albion Lowlander to the right