I brought an old case back to life as a gift, all new internals and adding hacking/ hand winding but keeping the weathered outside. There's a new bezel insert and spring available if they change their mind later
The NH34 movement is, as far as I'm aware, effectively a drop in replacement for NH35/36, although may need a taller crystal to accommodate the taller hand post. I'm pretty sure a couple of microbrands are already putting out watches using them
Budget Saturday- Casio Duro + Aliexpress bracelet