Since it says that the arm receives no bonus from other ways to enhance unarmed strikes, such as an amulet of mighty fists, I would say no. But that’s just my humble opinion.
My question is that if it is considered an unarmed strike, which is a light weapon, how can it have the impact special ability for the magus to choose? I’m just wondering if this could be used with the Dancing Dervish magus we’ve all seen before?
It does mention that for the purpose of enchantments it can be granted by spending a point that it counts as a manufactured weapon, not just unarmed strike.
They also state that for the purposes of remaking it out of special materials to use the statistics of a heavy mace for weight and price.
Very true. But unless otherwise stated enhancement bonuses do not stack. Since you get enhancement bonuses already under the normal progression I don’t know if you could further add to it. Now if you were to add special qualities that might work, for example holy or axiomatic.
It’s similar to how a blade bound magus works and it might be worth to check out if they can enhance the weapon faster than on the chart.