Re: youth .260?
260 is a perfectly reasonable caliber to start kids deer hunting with. I started with a 7mm-08 when I was 9 or 10 and didn't have any trouble. 243, 260, and 7mm-08 are all based on the same case and are all good caliber choices.
Everyone has a different idea of what economical is, but for a young person's rifle I would look at synthetic stock and all stainless metal. Remington is a classic choice (700 only... don't fall for the Model Seven) but for a stock, factory rifle I might look at the Tikka T3 or one of the Savage rifles.