Why not go to ACE for the stock, get the folding mechanism, buy the correct adapters from either ACE or Kerbs, then use either the ACE skeleton stock, ACE Ultralight/entry, or use a milspec buffer and put any AR15 stock on it? I have this setup on an NPAP and I love it.
I don't have any experience with stormwerks but I do own two TWS dogleg gen ii rails on M70's that rock, they lock up very solid and return to zero. I see they're available for the M92. Something I think is important for a hinged dust cover rail system is a secure attachment method for the rear of the rail or the dust cover will have some play in it and will the optic on top. The TWS takes care of this with a proprietary takedown button which is angled and puts constant downward pressure on the dover preventing up/downward movement. There is also a slit in the dustcover on the right side that puts constant pressure on the dustcover to the non ejection side and prevents left/right movement.
If it was me I'd just go with the Ultimak top Manticore bottom and mount the red dot forward on the handguard.