[Arran]

I would have selected metal film resistors over 1/2 watt carbons, the tolerances are higher and they don't tent to drift as much, they are also reasonably cheap. Most meters used precision resistors, as yours did, they did of course have carbons at the time but they were dot code types and were off by as much as 20% the day they came off the line. More then likely someone accidentally had it switched on ohms when they tried testing high voltage, it will almost instantly take out the bottom resistor in that stack. If you just wanted to get it working for display it doesn't matter, but for a day to day work horse it could.
Best Regards
Arran