Any DAC better than the MF A324 Upsampler?

I suspect in your price range you are just fine where you sit. This is not a bad place to be, so enjoy!

I would try and get hold of a Northstar Model 192. The A3 24 is a bit flat and dull unless the one I heard was a bad 'un. I thought the Northstar was far more musical, but I cannot guarantee you will agree. One nice feature is that at a later date you can get a DVD Audio player and have a MSB Network card added (USD600) at some point and that will give you a low jitter I2S interface for the Northstar to decode the DVD Audio stream at full resolution.

If you don’t need to decode 24bit signal, I would recommend a used Theta Gen Va. I know it has been out for a few years. But IMHO it is still one of the most musical DAC around. I have seen it listed here for as low as $1,200. I don’t know how one can do better at this price, used or new.

The Electrocompaniet ECD-1. About $1250 used. It holds back a little in high-frequency dynamics, but otherwise perfect. This can be fixed with mods BTW.

Are there any MF Tri-Vista 21 DAC's left?

It's really nice. I had a Theta Gen III and traded it for a Conrad-Johnson D/A-3 (about $400.00 used) that blew the Theta Gen III away, I think. In fact, before I traded mine in on the Tri-Vista, I had the dealer hook it into the MF Tri-Vista SACD player, and I couldn't hear a big enough difference with CD's that made me even consider going that route.

But the MF Tri-Vista 21 was a completely different story. I'd suggest that first.