No, a 2915 crown would have the naïad Mercedes sign and 26 teeth.
Many available Flat Foot crowns need to be adjusted to fit a 321 movement as they might be a Railmaster (2914) or Seamaster300 (2913) crown. The pertinent stem sizes are
Speedmaster, 321 caliber, 1.0mm
Seamaster300 (2913), 501 caliber, 0.9mm
Railmaster (2914), caliber 284, 1.2mm
The stem sizes are:
2913 0.9mm, caliber 501
2915 1.0mm, caliber 321
2914 1.2mm, caliber 284
Additionally, most research (including MWO) and examples indicate that the 24 point, 6.7mm Flat Foot crown was the OEM crown on the 2915 Speedmaster.
The Naiad Mercedes type is more prevalent on the 2913 SM300 and the 2915 Railmaster.
As the Naiad was thought to be more water resistant it would have made little sense to install on a 2915 with leaky pushers.
