Time to retire my McCormack DAC-1 ?

DAC technology keeps moving in leaps and bounds.
I, too, love Steve's work, but I think the DAC stuff isn't as much his specialty.
One of the best DAC's for the money, IMHO, is the Ayre Codex, which you can find used for around $1K.
The other would be the Schiit Gungnir or Yggy. A bit harder to find used (with current upgrades), but worth the money.
Like Ayre, Schiit provides upgrades to their equipment when they find it makes a significant difference.
Bob 

@OP,
Schiit offers a wide range of DAC's at various price points, but the Gungnir and Yggy are second and highest priced models and perform beyond their price point.
My choice is the Ayre Codex, which you can find used near $1K, sometimes below. And, customer service-as with Schiit, is very good.

You might want to check out the Bluesound Node. You don't need the latest model, so buying used is available. I was just looking at the offerings and it has Tune In- which has radio stations around the world.
You can either use the built in DAC in the Bluesound or output to a separate DAC, like the Codex, and get high quality sound along with a wide range of music services.
Bob