Can you help ID this Helios movement?

[EelDahc]

It has "Helios" stamped, on the left side of picture. Then it has "WATCH CO" with "SEVENTEEN JEWELS". The marking under the balance cock is the letter "D" and it has "315" just above it under where you see "SWISS".

Closest I can find is Bifora caliber 934 or Dugena 704, going by the little top plate.  10 1/2 size

 

 

 

[WatchMaker]

Helios are associated with Precimax (as are NPX and Perfecta).

Certainly this looks Precimax like if you consider: http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&2&2uswk&Precimax_250

But I can't immediately see a 315 variant.

A pic of the keyless works would be useful.

[EelDahc]

That's it, Thanks so much.