You could always hop over to https://frame.work and pick up a refurbished Intel mainboard plus an enclosure (or 3D print your own using their plans). You’d just need to get some RAM and a small SSD to run an OS like TrueNAS and you’d be good to go for probably under USD $600.
Gosh, if only we had some sort of deal that resulted in a solid framework that would have prevented Iran from further nuclear weapons development. Maybe something like a Joint Comprehensive Plan of Action?