What can I do?

I grew up on Skyline. I always pick up Skyline Chili Spaghetti dinners when we shop. I was eating one the other night and after I took a few bites and on the last bite I noticed something hard in my mouth. I pulled it out and it was a small silicone rubber ball thing. It actually made me nauseous. I know it was probably just because I have a weak stomach, but I also know I'll never eat Skyline again. I approached them with my complaint and they want me to send the object to them (which I refuse to do) and allow them to repay me for what I spent on the dinner (I also refused that). I still have the entire dinner with the rubber piece in my fridge.