How much per person?

If you are serving in the roast tenderloin with the noodle salad, there are other ingredients to bulk up the meal like the noodles and other vegetables like cucumber, carrots, beans (per the recipe). I would estimate that roughly 3-4oz per person. Noodle salads were pretty much designed to stretch the protein to feed more people since meat was and still is expensive. I would also suggest slicing the pork very thinly for this salad. You'll find that you need less meat and still be quite full with the salad.

Half a pound per person when meat is the main star in a meal, and 1/4-1/3 lb per person when meat is a part of bigger meal, like an ingredient in curry or pasta with lots of other ingredients. https://www.thekitchn.com/whats-the-right-amount-of-meat-to-serve-per-person-112577