I went the whole hog and used 8 PSL-30N-5W2 buttons. They’re great as they come with a multipin connector on the back making it easy to get them back out again.
They are expensive. But in reality, a build like this is certainly in my case, one of a kind and something of a centrepiece in the room.
Because I had my iron out anyway, I’ve wired mine into the 5V header on the pi itself. I’m driving my picade from an anker 6 port 2.5A per port charger. It seems to be working fine for the purpose. I did run out of juice with a single 2.5A pi supply but only because I’ve also added 14 or so WS2812’s at the top to illuminate the marquee and buttons from above.
Take a look at mine if you want, details HERE