Size of receiver is way to big to fit in camera housing. Plus Im a little concerned about trying to send radio waves through the water. Although I guess with such a short range it may not be an issue.
Size wise I am restricted to the size of 2 AAA cells including the battery for the circuit. SO if I can build it to the size of a AAA and power it by another AAA sized Li Ion it would be perfect.
Im guessing I just need a AT tiny and an IR receiver diode wired up to a AAA Li Ion and a 8 pin USB