HTIB for $300

I'm currently looking for a HTIB to hook up to a Optoma HD70 projector. From what I can tell, there is no TV tuner in the HD70 so I need to find something that I can plug my coaxial cable into. I need all of this and need to keep it around $300. Also, I'd be open to any suggestions of trying to hook up a cable box of some sort, I just have absolutely no idea of where to even start looking as this is my first home theater project. Any input from you guys would be greatly appreciated.