Yes, I'm familiar with second-source 6502. Also, I've seen the Rabbit2000 processor, it's basically a Z80 running at 50 MHz. But I wasn't aware that 80286 has any modern second-source clones. Are there?
Fun thing: I remember a 40 MHz 286 desktop at one point. Wikipedia tells me they only went to 25 MHz. That's some overclocking...
Fun fact #2: with a feature size of 1.5 µm, one could fit an entire 6502 done in 7 nm process on top of a single 80286 transistor.