One of the requirements is:

At least a 250 watt 12v power supply with a 6 Pin PCIE connector is required.

I could use some help sourcing this. Does anyone have any recommendations or suggestions?

I looked on eBay and there are a lot of power supplies offered.

I did find this one though:
https://www.ebay.com/itm/HP-659193-001-Elite-8200-RP5800-240W-6-Pin-Desktop-Power-Supply/202373513718?hash=item2f1e66c1f6:g:UeIAAOSwhclbT6Fj
Would this work?

Any help would be appreciated.