You can have light supernoodles which can be made in the microwave at work.
Also rice with veges is nice - you can have this hot or cold. Mini quiches from the recipe section are good.
ASDA pitas are 1 healthy extra B so you can take one to work with a salad. I have a salad everyday but you can mix it up with different meats, adding different salad, hard boiled egg, new potatoes, try different FF/low syn dressings
There are some really nice looking quiches in the recipe section that you could bring in?
Muller light yoghurts, fruit and other free picky things also are good, even if your main lunch is the same if you mix these things up it seems different.