More details can be found here:
The keyboard is available as pcb only, assembly kit with all parts and full assembled version (ready to use) on sellmyretro.
This is not a directly replacement or spare part of an original ZX80 but can be fitted with manual wiring.
I don't think someone will do this on real ZX80 but it can be used for a modified ZX81 (with ZX80 rom) or for own purposes/developments.
Just in case someone needs.
This is available as assembly kit as well.
Or all other items here:
There is only the completed/assembled version available but with lower price (same now as previous kit price).
So assembly kits and pcb only are no more available as all boards have been assembled in industrial way.
The replacement keyboard is now EUR 17.90 (was EUR 22.50 before) with ZX81 membrane or EUR 19.90 with ZX80 imprint.
So it is same price than the ZX80 membrane or 50% plus in comparison to a simple ZX81 membrane.