I can do it.
It would require a power mosfet as switch and a simple microcontroller with a program that tells him:
"Hey you! when you receive power wait for some time, flash X times a LED or do somthing to indicate turning on, and then give power to the gate of the power mosfet to power da laz0r!
Not hard to do, and for less than $2 or $3. Using a timer circuit will be useful, but would make the circuit bigger.