What I found instead is even nicer, a 9.600MHz crystal, together with a 6.000MHz one, even in one bag. The 9.600 xtal looks like I salvaged it once from something. I would not recall what, possibly some obsolete network gear.
I guess, the design of the 80m secondary frequency MEPT is hereby decided. Nice in this is, with actually using the difference, some drift cancels out.