Sure looks like a moulding head to me. I notice that the blades seem to be centered, with a little overhang on each side. You may have to make a new insert for it. After installing the blade, please give it a spin by hand to make sure it clears the cast iron table (left side). It may have been originally sold with a shoulder washer to flush the left side of the cutter with the arbor shoulder and to provide clearance to the table top. If it makes any contact, do not use it.
Moulding heads look and sound scary, and do present a significant hazard of kickback. They can safely be used using kickback protection (featherboards, etc) and by taking shallow cuts (no more than 1/8" per pass).
A tip to using them successfully: make sure you read the grain and have the grain running with the rotation of the blade. If you have a knot or other grain reversal, take very light cuts per pass If you make a ZCI, run the blade up to full heighth thru it before using it. Moulding heads have a tendency to tear out chunks of wood if they hit any grain abnormality, and will try to bury that chunk in the insert if there isn't enough clearance for it to pass thru to the bottom. It it can't pass through, it will probably end up under your work causing it to ride up. If you have good kickback protection providing downward pressure as well, it can jam your work. DAMHIKT!
HTH's
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