Both MEA Boeing 720s and the Air Gambia 707 did quite a lot of sub-charters in the mid 1980s. When the Air Europe 757 had its mishap at Funchal in 1987, they ended up using the Air Gambia 707 still in half Air Mauritius colours and a Zairean-registered 707 from Scibe Airlift on subcharter flying in formation to cover the schedule. [Lord only knows what the CAA and any airline compliance department would make of such wet-lease activities nowadays.]
We'd flown out on holiday to the Canaries on G-BLVH a few days before its incident in Funchal and ended up quite badly delayed on our return with AE flights from Arrecife to both Gatwick and Manchester due to leave at much the same time. The Air Gambia and Scibe 707s both arrived in ACE amidst much noise and black smoke flying for Air Europe which raised my hopes that the return trip was going to be quite exciting ... until 757 G-BPGW then rolled up as well - and guess which one we ended up on!
The British Midland 707s did a whole series of Los Angeles charters in 1984 for the Olympics. I think it was early 1985 when G-BFLD, BFLE and BMAZ as the remaining trio of 707s were retired.