Mattel Electronics Football - screws

[nadir]

Wow!  Was shocked to find that the Mattel Electronics Football handheld that I thought had been discarded years ago was still in my Mom's garage!  That's the good news.  The bad news is that the always hard to operate power switch (3 position for Pro 1/Off/ Pro 2) snapped right off when I tried to move it.  I'd like to at least turn this thing on to see if it still works/is worth salvaging.  The case is pretty yellowed, but otherwise seems to be in good shape.  The issue is that it looks like someone has tried to take it apart before as the screws on the back show some damage.  Likely damaged from someone using the wrong screwdriver as they appear to be special.  Perhaps a triangle or maybe a "Y" head on them?

 

Does anyone know exactly what kind of screw came in these so I can obtain an appropriate screwdriver for a disassembly attempt?

[+fdr4prez]

This probably has it:

 

[nadir]

I ended up being able to verify that they are in fact triangle by finding eBay examples and zooming in.  I was then able to get a basic six pack of triangle bits from Amazon for disassembly.  Unfortunately, the slider switch is somewhat specialized in size and design.  However, I was able to break it loose so it operates again, just the post is snapped off.  I've been able to operate the game by jamming a screwdriver into the hollow left when the post broke off.  I found that the game has a partial display failure.  Non critical area (just part of the score that you can usually figure out anyways), but I'm not going to invest the time into a full repair due to that.  I'll just keep it around for funnsies and use the screwdriver to activate it!