best DAC for streaming to my 2 channel system?

What do you have now? Are you new to streaming? As mentioned above, your question is hard to answer. Only you can say what sounds "best" in your system.

If you are new to streaming and have no DAC at all, I suppose you just need a place to start. A $1K budget is nothing to scoff at and there are a lot of options out there.

I'd suggest trying to find a local dealer that will do auditions, letting you take a unit home to try it out before you buy something. If you can't do that, stick to the used market, that way you can try something and sell it if you don't like it.

I've found that when I'm trying new gear, it usually falls into one of two categories. Either I like it or I don't. If I don't like it, I either get rid of it (if I bought it) or take it back, if I can. If I do like it, I keep it, until I find something that I like better.

Personally, I really don't think that there is any "best" out there. For me, it's because my tastes change or I just feel like listening to something with a little different character. For me, finding a piece of equipment that suits me is a matter of settling on a piece of equipment that is the best I've heard for right now.

I'd say, do some reading and find out what suits most people and start from there.

Well, it seems that you like Rega equipment, and rightfully so. Perhaps whatever it was that you listened to or a Rega DAC would be in order. If memory serves, the Rega will accommodate coax, toslink and usb.

There may be many who will disagree with me, but I've found that once you get into a price range and stick with reputable manufacturers, the question becomes one of what you prefer; and less a matter of trying to avoid crap equipment.

If you can buy used, I wouldn't burn up too many brain cells on this issue. In your budget range, there's lots to choose from and I'd say that ALMOST all of it is going to be at least good.