Integrated for Legacy Audio Focus SE's

Start with a BAT VK-3000SE (150/300 8/4 ohms). If this doesn't work, add a VK-220/225 SE and bi-amp (doubles your power). Bi-amping is extremely easy with the BAT integrated using its pre-outs.
BTW, great sound as well.

Legacy used to display with Coda. Coda used to produce the Legacy amps when they were class AB designs. Consider the Coda CSiB, it should drive them just fine. 400 WPC into 8 ohms, 800 WPC into 4 ohms.

Without a mention of budget, your question can’t even begin to be answered... also, what do you need in your int? DAC, phono, etc? 

As a prior and very happy owner of a pair of Focus SE's,  I can tell you that the only way to really wake the bass up is to feed these speakers with alot of power.  A 250 watt/side class A/B did it for me.  As to what Integrated might fill this bill, Pass Labs, top end Accuphase - or - consider running them bi-amped.  Final option you might consider is selling the SE's and uplifting to the XD's (internal powered woofers).

Thanks for all the comments. I’m not so much looking for suggestions, although I do appreciate the BAT and Coda thoughts, I’m more interested in those who use an integrated with their Focus SE’s and their thoughts about it. I do agree with jgwilson, the way to make Legacy’s really perform is with lots of power (despite their efficiency). I have that now in my separates but would like to "downsize" to an integrated if I can find one that is really outstanding. I wanted to try tubes but I’m not convinced anything is powerful enough. That makes the BAT interesting. One other unit that’s been on my radar is the Ayre AX-5 twenty. I’m not so concerned about price right now but rather finding a real performer of an integrated. I should also mention that I do not need a dac or phono input.

Pass Labs XA250.8... there really are a fair amount of great integrateds that will run your speakers. Another great option is the Hegel H390 or 590. I’ve only run valve pre’s with SS amps so no help there with a valve int.