As others have said, the SET option at your power and price requirements doesn't exist (Aric will come in much higher in price by the time they create a customized integrated for you more than likely), why not a Prima Luna and call it a day?
Considering A 20-40 Watt Stereo SET Amp
I just got over a 16 day illness (not Covid) where it was touch and go for a few days. I am thinking of rewarding myself with a 20-40 watt stereo SET amp. The speakers I will use are a pair of the new JBL L100 Classic speakers that I bought at the end of 2020. The speakers are rated at 4 ohms @90db sensitivity.
Presently, I am using a McIntosh integrated and I do not listen loud. The meters on the Mac usually sit between .20 and 2 watts at its loudest. I have not started looking yet but I do know I want something with 1 pair of outputs so I can use my SVS powered subwoofer with it. I would also need 3 high level inputs. I don’t want to break the bank as this would be a secondary amp to put into rotation as the mood strikes me.
I do not want a flea powered amp so it has to be 20-40 watts and under 4 grand new. Used would be even better. I am hoping I can be steered in the right direction so I can start my research. I do not want to have to buy other components to accommodate the amp. Source components are a McIntosh SACD player, McIntosh FM tuner and a Sony HAP-Z1ES music player. Nordost interconnects and Canare speaker cables, Shunyata power cords and a Furutech power conditioner round out the system. The amp must be stereo, no monoblocks please. 99% of my listening will be through my Mac FM tuner. The system is also on its own dedicated 20-amp circuit.