Pine A64 not powering up / Power button missing

[vaevictis]

I assembled the case and powered up the board, download the Debian image and used Win32 diskimager to write the microSD card. I use a 2.0A, 5V power supply.
The power led turns red, but I get no signal on the TV. 

So I read that a separate power/reset button should be included but I didn't find any in the box.
How do I turn on the Pine64 without a power button? And how can I get the power button replaced?

Thanks.