This becomes much easier if you are open to doing the organs in software. Use the MIDI out from your digital piano.
The SK lacks loudspeakers, in-built temperaments, (I think) church-organ-like touch, and portability with all the extra equipment. I’d gladly prefer an all-in-one solution.
”I’like to buy a digital piano”so a need the piano, with capability of a decent organ and harpsichord sound, … and without stand.
I have not found one with a convincing organ sound at any price. You're trying to get one keyboard that will do two or three things well. You want a portable piano that can also emulate a quality organ that also has good speakers.
3. an actual portable organ like a Hammond B3, but now it won't sit on a table.