Budget amp recommendation needed

Looking for an amp or integrated in the 500-700 dollar range used. Will drive 78db speakers playing all kinds of music but more weighted toward indie, alt-country, and alternative.

Appreciate any suggestions.
Odyssey with upgraded caps (120K).
Are you sure about the 78 dB efficiency figure? You would need LOTS of muscle if that's correct. You might get lucky and find a McCormack DNA 1 at the high end of your budget. OTOH, if its actually 87 dB, then a used DNA 0.5 which to my ears is a better-sounding amp, would probably will the bill @ 100 WPC.
78 dB has to be wrong. Also, are you talking about a power amp, which has been suggested above, or an integrated amp? If the latter, two come to mind, Rega Mira 3, and Portal Panache (if you don't mind the lack of a remote).
I like McCormack and B&K amps, lots of muscle and fine sound.
CJ MF200 here for cheap. Owned 1 puts out 250w a side.
Liked it better than Odyssey.
At your stated price range, I think it is very difficult to do better than a Musical Fidelity A300 integrated amp. Run $7-800 used, put out 150wpc. Have mm/mc phono input and remote. Don't need $$ for interconnects between pre/pwr.

I personally like the sound of MF A series (made in England).

You don't mention the specific speakers or your source, but this is my $.02.

A second for the Odyssey Stratos w/ 120K caps, available right in your price range. Will drive most anything, has lots and lots of current. If you lean towards soundstage, dynamics, and detail, hard to beat. Not very warm, though, if that is your preference.
What speakers are those with the 78db rating?
Aragon 8008BB competes with VERY high end gear. In your price range though you'd be looking at the ST. 78DB is absurdly low sensitivity though....what are they?
Thanks a lot for the responses. The speakers are actually an old pair of JBL l100's I can't seem to part with. The specs say 78db but that is at 15 feet. From what I've read, that is more like 90db at 1 meter.

I've run the speakers on all kinds of amps/receivers and they really seem to open up with a 100WPC or so.

I am also looking at some Vandersteen 2C's that could end up in this system at a later date.
If you an get your hands on one A S/H ME 240. There happens to be one on eBay Australia right now. The one for sale is the standard model. I owned the remote control Hi cap option version. I don't know the seller so I cannot comment on the actual condition. All I know is when I owned it I loved it. It was my first real taste of high end amplification for speakers anyway.
Biased at about 2.4 watts RMS in class A with precision A/B switching for a total of 90 watts RMS into 8 Ohms and I measured 125 into 4 Ohms. Point being this little freak sounds as good as the early Krells that I have heard and features technology that still makes most modern high end look agricultural. It may look svelte but it can deliver 42 amps into transient musical peaks. It sounds way more ballsy than the ratings suggest. You likely haven't heard your JBL's at their best yet. You will with this. Problem for you is that you would need to run a step up transformer for Aussie 240v Small price to pay for sonic bliss. Into tubes now and only run transistor amps in my computer room. Cheers
With the sensitivity of JBLs you can use whatever you want except for SETs flea watt amps. But really very little I mean than 25-50WPC int. amps and receivers should be OK.. Did you specifically say SS no tube or just an Integrated.
I will assume SS.
Old school Macs that have been well kept. There was one model the MC2105 that was made for a dozen years that you can find in tour range. They are usually underated at 105 W and bench higher like most Macs. The downside is the bang and sizzle. It favors the dynamics over the details and stage.
The Plinius 8200 might be lurking around for that and the Classe that is about 7 years old now are two more.
I owned a A308 Musical Fidelity and at 150 watts and current out the yazoo has muscular drive. It is a good choice for clean sound. It was a little too stark at times for my analytical speakers.
If you wants gobs of power the Aragon 8008 will do the trick. I had Palladiums at 400 WPC suposedly in class A up to 125 watts, They will drive very low sensivity speakers well but didn't sound like they were in class A ever. Further they run a little out of your price range and require a preamp.
I found that what finally made me really happy, was an all tube set up with adequate power. That's a different ball of wax.