Magneto plate may have make model and serial number
of the magneto stamped into metal. Look on bottom of magneto plate to see what if anything is there.
Wico,Eisemann, Bendix were so marked. Phelon has
model number stamped into top of flywheel.
Most outboard makers purchased carburetors and magnetos off the shelf from vendors so frequently
brand A magneto on a brand X outboard is pretty
much the same as brand A magneto on brand Y outboard.
Louis