Suggestions for a streamer only (I have a great DAC)

I have the same need as you.  I found nothing that was streamer only at an affordable price - - similar to your budget.  I looked at all "the usuals," Aurender, Lumin, Innuous, and so on.  Finally, I looked at Antipodes - but a mid-range model with power supply was $7K. 

While I made inquiries at Antipodes, I also began taking a close look at LDMS, who makes streamers only of very high quality focused use, even custom order per user needs/specifications.  And they are very experienced with Roon.  The Pico model is under $3,000.  The next up their line is $6,700 (but what is included is amazing).  It has been said that of this unit even as streamer only is preferred over other streamers/severs in the $15K to $20K, as remarked by audiophiles who moved on from some of the brands I listed above.  

Bel Canto e.Stream, $1200 used.

At your local dSC dealer you should be able to trade your Paganini and clock for a new Bartok.  The Bartok has an updated dCS ring DAC and streamer.  You can use their Mosaic streaming program to access Tidal/Qobuz or subscribe to Roon.  Top quality sound and economical.  Or, spend some additional money and get a Rossini which also has streaming capability.  Both units will continue to receive dCS software updates which have stopped for the older Paganini.

ifi zen streamer. 

If you are after just a streamer then look into what Auralic has to offer. I believe the Aries G2.1 is one of their top tier offerings. If you were interested in possibly abandoning your DAC then I suggest looking into on of the Bricasti units.