This is the backside - no markings or parts numbers on this whatsoever.
Notice the indention at the curved portion of the plate. It appears this "crescent" holds down the plate while the full circle holes stablize it from shifting latterally. The placement of the holes is identical to the Brother machines I know about, except for the orientation of the feed dog slits to the straight side.
Frontal shot of the bobbin mechanism. Notice the "12 o'clock" placement of the stem.
Back side of the bobbin case. It's hollow between the black plastic back and the metal front.