Bedini back in business?
If you have any DIY skills, consider these. I made half a dozen of them - and still use two of them in my HT, running Magnepan MMW. Clear, musical sound and dirt cheap. The better the parts, the better they sound.
If the link doesn't work, Google "J L Hood amp for Quad".
Near everyone goes for tubes with these, but a Sugden A21SE integrated or the Bedini will garner some very good results. Both Class A. The Bedini of course will be aged and suffer from degradation like any electronics.
The VTL Tiny Triodes were dynamite. Very quick and musical with surprising bass control. I love EL 84 based amps. Best of luck in your search.
OP, with such programme material, you might enjoy addition of air, separation, and greater front to back spatial rendering, trying Max Townshend's Supertweeters. Designed specifically for ESL57's. Listening to the kind of music you note, even, at low volume in the evening resulted for me in a magical bath of sound. (Electrostatic Solutions rebuild at 89dB efficiency and 4W + 4W ADI valved SET, (15' x 13' x 10' ceiling room)). The SET was part of the magic. Alas by comparison my rebuilt Quad 303 was dry with markedly reduced colour. If you go the SET route, check with amp and valve / tube manufacturer on long term operating conditions. Alas, I had no space for my 57's, and so they went to a very happy fellow listener.
Original Futterman H3. Quicksilver Minimite Monoblocks, Antique Sound Lab AV 25 Monoblocks.
The Bedini 25/25 is known for its synergy with the ESL 57. What may not be as well known is that the Futterman H3 OTL was also highly recommended for use with the Quad 57. I’ve never owned a pair of 57’s, but I did own an H3 and early 25/25 which I used to drive 15 ohm Rogers LS3/5A’s. These we’re both successful pairings.
Owning both the ASL AV25 and QuickSilver MM mono's, I would think that they would also have a great synergy with the ESL 57.