Recommend me a small SBC!

So I'm looking to do an improved version of this project from a couple of years ago that rebuilt the dreamcast VMU into an emulator system that could even interface with a modified dreamcast controller using the original connector. That project was really neat, but it used a raspberry pi zero, which is frankly anemic for running any emulators past the SNES, and I'd like to find one that's powerful enough to emulate the dreamcast itself, but small enough to fit inside a VMU. To that end, my requirements are:

• Must be of a similar size to the pi zero. Smaller would be better, but it absolutely cannot be more than 40x65mm.

• Must have a processor at least as powerful as a cortex A53, preferably something more powerful like the A72.

• Must have a release of armbian (or similar) with drivers for full video acceleration.

• Must be able to drive a display over SPI.

• Must be available. The NanoPi NEO Core 2 is pretty close to what I need, if maybe a bit underpowered, but it seems to be discontinued and I can't find it anywhere but aliexpress at double the list price.

• Composite video out would be nice.

• Analog audio out would be nice.

• Availability without soldered headers and large ports would be nice, like the pi zero or nanopi neo.