Odd PSU Question - Seeking Recommendation

Alright, to get down to it - I'm recovering from a very nasty breakup (where I lost everything but the kids) and I'm finally getting my stuff back together. I have a Barebones system that stayed with me, that I've intended to turn into my workhorse, but I need PSU recommendations. It has to be 1U, at least 450 watts, preferably 500 watts, and have connectors suitable for a GTX1080 class card. I know EVGA had FSP customize something like this for their now extinct Hadron series, but does anything like this still exist?

Is this a 1U server? Got pics?

It's not - it's an MSI Nightblade MI2 bare bones kit. The included PSU is a customized 350 watt FSP 1u design, but I'm not super comfortable feeding my i7 6700 and a 1080 with just 350 watts. I know it can be done, but it's gotta be right up against what the PSU can safely output.

Maybe something like this Shuttle 500W PSU?
https://www.amazon.com/Shuttle-Accessory-PC63J-Supply-Barebone/dp/B0047DFX7Q?th=1

That's a FlexATX PSU, and a bit of googling around shows the MI2 probably uses a FlexATX PSU as well. Gotchas will be cable lengths, and the Shuttle PSU has a 20pin ATX connector. So you might need some extensions and/or a 20->24 pin ATX adapter for the MI2.