Bad news! No simple dc-coupled IR LED and IR detector has a range of 5ft, unless it has very complex optics with beamwidths of less than a couple of degrees (making hard to align). The IR detector is usually swamped by ambient radiation from lighting and sunlight.
The only viable way of getting a range of several feet is to use the method used in IR-based remote controls such as on your TV set, where the emitter LED is pulsed on/off at an ultrasonic rate (usually ~40kHz), and the detector is AC-coupled to a narrow-bandwidth, high-gain amplifier tuned to 40kHz.
Good news is that the detector is available as
an cheap IC.
Read this thread; it talks about how to build the transmitter.