Tarom of Romania. El Al also operated into Bucharest in return as well.
Spot on! I found out about this via a coworker of mine who flew a TAROM 707 into Ben Gurion in the early 1980s
Tarom had a widespread fleet, both Soviet and Western types, in addition the final One-Elevens were assembled in Romania at a large plant which seemed to manage an average of one aircraft per year throughout the 1980s. They had further One-Elevens which had been built in the UK.
They operated various operations into the UK at this time, you never knew what type was going to turn up, it varied from flight to flight. Their main service from Bucharest to London Heathrow operated a few times a week, generally through other points like Brussels, and it would be a One-Eleven (as scheduled) one time, next a Tupolev 154, next a 707, and so on. They also operated summer holiday flights from Constanta on the Black Sea coast to Gatwick, Manchester, Glasgow, etc, typically at weekends, which could be anything, and at the start/end of the season might actually be an Ilyushin 18 turboprop, well into the 1980s. Then any large group, which seemed to be one of the few ways for regular Romanian citizens got to Britain, like seamen for a ship crew change, or some oddball entertainment group, would often get a charter flight of their own, the sailors going to the nearest point to their ship, which would bring them in to secondary airports like Liverpool.
Quick supplementary bonus question. Which major European airline started their jet operations with a fleet of One-Elevens leased from Tarom ?