I've been trying all over the place to find the proper eyecup assembly that threads into the DP1 or DP3 viewfinder. Even the troops at B&H or Nikon can't figure this out, or Moose Peterson for that matter. Is it the rings from an F3 viewfinder and the eyecup # DK4, or DK3? And....does anyone know where I can score about three or four of these rigs? Insight (vs. eyesight) would be appreciated.