This month's issue of Cooking Light has a recipe for traditional three bean salad in it. Here is the list of ingredients:
1/4 cup cider vinegar
3 tbsp grated onion
1 tbsp sugar
3 tbsp olive oil
2 tbsp dijon mustard
1 tsp minced garlic
1/2 tsp dry mustard
1/2 tsp black pepper
1/4 tsp salt
1 lb slightly steamed green beans (crisp-tender), cut in 1-inch pieces
1/2 cup minced red onion
1/2 cup fresh flat-leaf parsley
1/3 sliced green onions
15 oz can great northern beans (rinsed and drained)
15 oz can kidney beans (rinsed and drained)
The instructions are to mix all the ingredients together and chill for 4 hours.
It makes 7 1-cup servings. Nutritional info per serving: 207 calories, 7 g fat, 1 g sat. fat, 8.5 g protein, 29.7 g carbs, 9.2 g fiber, 368 mg sodium, 0 mg cholesterol, 95 mg calcium.
The olive oil is accounts for about 50 calories per serving. I'd definitely be tempted to try this recipe without it. I might even try it without the sugar (although that's only about 5 calories per serving).
If you want to make this easier, you could used canned green beans (I'm sure that's what's in the deli salad), bottled minced garlic, and leave out all the onions and parsley. That way you wouldn't have to do any chopping or grating.