A friend of mine who flew a Grob 109 (G-UILD) was given a Decca navigator with about a 7 inch LCD display to try back in 1986; unfortunately I never saw it in action.
As for the 'rations'; I was allocated an ATCOs jump seat to Palma from Gatwick on a 767 one day. In accordance with the rules, all 3 of us on the flight deck were given different meals but I noticed that while the stewardess gave me a hot meal they only got cereal. I sat behind them tucking onto my tiny portion of egg, a small rasher and an equally tiny sausage while they looked round enviously so I asked how come I got the hot meal; they replied it was a sector length less than 2 hours so they were only entitled to a cold snack.