I can't make it out either. The Holbay lobes are much "flatter" on the top than the standard, but looking at your photos, I can't decide whether it looks more like one or the other

The only marking I can find in the standard cam I have here is "SF2".
The Tagora engine manual identifies the cam by two rings between lobes 4 and 5. I.e. nothing about markings. Depending on what "raw material" Holbay uses, it doesn't have to say anything.
If you compare with my photo here:
http://gallery.dinsen.net/v/biler/Murena/technical/engine/DSCF0005.JPG.htmlIt does actually bear the "FMA" marking.
If it is a Holbay, it doesn't look like it needs a regrind at all.
- Anders