Does anyone know what this type of power connector is called and if there are any after market alternatives? I think I could frankenstein it from a PSU even but not sure if that is a good option.
What is that type of pin called, the one that isn’t square but rather like a “house”, same shape as on some of the ATX pins.
I suspect this is what you’re looking for - looks like that’s just a regular Molex Mini-Fit Jr connector.
Molex even makes off-the-shelf cable assembles for some of them:
https://www.mouser.com/ProductDetail/Molex/215328-1021?qs=DuoOggApuK%2BmUcHtq8Kv7w%3D%3D
You should obviously confirm the size/pin pitch first because they have other connectors that look very similar (Micro-Fit, etc), but that should get you started if you decide to just re-terminate another 5V power brick. 
What model switch is that?
It’s an 819G router, comes with WWAN.
It very much does look like that one, thanks!