I've seen sprinkles go anywhere from $1.75 to $3.00 but chocolate sprinkles specifically might be a little more. I suppose it would all depend on the store. My advice, just look around and try to find the best price!
Hot Chocolate is relatively inexpensive. A box or container can cost between $5 and $10 (depending on the brand, quality, and amount). A mug of hot chocolate bought pre-made is usually a few dollars.