>>1 okay something like this has happened to me before, I used to be friends with a group of, well, "cool girls" so there was backstabbing and lots of bullshit. Anyways, no need to get into anymore unnecessary details, one of these girls stole a lot from me. She stole my favourite pretty expensive jeans and I loved them a lot. By then I had been fed up, she had stolen smaller things from me before but nothing that I really, really cared for. Anyways, I confronted her about it and she lied to my face. However, I had also talked to another friend of mine who was particularly close to her, and it so happened that the friend who stole from me had told my other friend that she had in fact stolen my jeans. My other friend told me the truth and we ended up getting the jeans back.
If I've learned anything from my experience it's that yes you should confront them, but not just the people you think are guilty but all of your friends individually and hope somebody tells the truth. Also don't be afraid to get the police involved or even threaten to get them involved. $300 is a lot of money so it's a pretty serious deal. Just remember to be 100% certain that the money was stolen and you didn't just accidentally misplace it.