Which DAC would fit me best?

I have been happy with the Apogee Mini-dac. It could replace your amp as it includes one. You can find them for $600-800 or so.

mhdt paradisea and replace the stock GE tube with a NOS Tung Sol equivalent for a more full range sound with better authority in the low end.

The DACMagic lifted my modest system beautifully, even right out of the box. Yes it's a fantastic bargain with features I can grow into. I've long been curious whether the 24/192 DAC in my player can be improved with an outboard processor and I'm happy to discover it did. Give it a try.

I personally think the Benchmark DAC sounds terrible - thin, amusical, artificial.

The MHDT DACs are all outstanding for the money. They are all in the NOS/filterless which to me is the best way to do digital.

I use a MHDT Dialogue at the office. $200.

Though I haven't heard one specifically, I'd second the Paradisea as it's MHDT and close to the Havana. I'm happy with the Havana after owning a Musiland MD10, a Benchmark DAC1 and Bel Canto DAC3. More laid back, albeit not near the jitter control of the DAC1 or DAC3.

At $400 I would look for a used Paradisea here on AGon. My Musiland MD10 (USB)($300 new)is great, but the Paradisea is better.

Just guessing, but I think the Paradisea would also beat the Dac Magic.

I've heard really good things about the $400 Cambrige Audio DacMagic - balanced outboard DAC. I've not heard it myself, but I know two people who told me that it is a fantastic bargain. It has been getting good press too. If I was in the market for a $400 DAC, I would definitely want to audition this one.
http://www.computeraudiophile.com/cambridge-audio-dacmagic

A 40 regular, maybe?

Used Benchamrk Dac 1 w/o usb - cheapest I have see here though was $675. Definately worth it if you can swing it.

The DAC1 from Benchmark has a good headphone amp. I'd get that if I were looking for a cheap DAC to use with high quality headphones. I doubt you will find it used for much less than $800 though.

I'm using the DAC in a Behringer DEQ2496 (I also use it for room correction), and the same DAC is available in the SRC2496 (whcih I am also using) for $200 new in the US. It does require use of balanced XLR to unbalanced RCA adapters since it is a pro audio unit. There are certainly better DACS out there but I like the sound for the price.

Thanks for mentioning the Little Dot MkIII headphone amp, I was unaware of these, looks really interesting for $200. I have a pair of Grado SR325 phones, the headphone output on the SRC2496 is OK, but it uses a lower quality DAC than the main analog output so it would be nice to have a better sounding headphone amp like the Little Dot.