The new Naim streamers all promise to be Roon Ready, meaning they will fully function as endpoints, so you might just want to wait; rumor has it the NDX 2 will be released around August and be in the $6-7K price range. Basically that's my plan, with the NDX 2 replacing my current ND5xs. I already have a XPS level power supply but will eventually go for the real deal.
In the meantime I recently bought a Lenovo compact desktop for around $650 which I've dedicated to being a Roon Core. It came with a 240 GB SSD, 7400 i5 CPU, 8 GBs of RAM and Win10 Pro. Setup was a cinch following Roon's instructions for migrating the Core from my general purpose / gaming desktop. The little Lenovo has a fan but it's almost completely silent; network connection is via Ethernet. So Roon now outputs 24/7 to all my devices like iPhone and iPad, all the Mac and Windows computers on the network, and via Airplay to MuSo and a linked Aries Mini system in my TV area; so far so good and the Core's performance on the Lenovo seems on a par with the previous much more powerful system.
Still working on how to go direct to my Naim gear; I have a much older Mac Mini which may have optical out which I could input to my nDAC; failing that I could use the headphone out to RCA inputs on my 282 preamp. In either case as the Mini will function as an endpoint, not the Core, its spinning drive and dated i5 CPU should be more than sufficient, the question will be if there is no optical output how good the Mac's built-in DAC + headphone amp output sounds.
Still it's just a temporary solution until the new NDX 2 is released at which point I'll retire the the Mini, the nDAC + PS, and reduce my box count by 3. As Thoreau says, "Simplify, simplify!"