A Valiant would have only been able to arrive at Eastleigh and as there isn't one still there I presume one didn't. They would, as I once did, go to Nairobi International, Embakasi. That had the luxury of, IIRC, a 12,000 runway and the best in flight catering I have ever experienced.
Take-offs were different. Bomber Command runways had a line painted across the runway at 1,500ft as an acceleration check point. Normally, then, you were at about 80 knots or so. Embakasi had no lines so we chose a fire vehicle access point that was 4,500 ft down the runway. AT 28 Celsius and 5,000 ft altitude the speed there was 85 knots. Water Meth injection was selected as we started the take off roll that gave us an extra 1,000lbs thrust per engine. It lasted for one minute and it ran out just as the mainwheels left the runway. We very nearly did two take-offs.
Embakasi opened in 1958 so your pictures would be after that. Colour slides were not common (or affordable for aircrew) until 1960/1 and as the squadron folded in 1962 it was almost certainly during that time.
Where 213 went to after 138 folded I do not know. I did not fly it at Gaydon and it was too old to be used as a tanker. It may well have been stored at Keevil until it was broken up. 7 Squadron's Valiants were stored at St Athan until the Grand Scrapping.