This topic appears to have been often discussed, and the answers I see are typically "no, it cant be done, an unarmed strike is not masterwork" and that masterwork transformation cannot be used to make an unarmed strike a masterwork weapon because "there is no such thing as a masterwork unarmed strike"
But where is it substantiated that there is no such thing as a masterwork unarmed strike?
http://paizo.com/pathfinderRPG/prd/ultimateEquipment/armsAndArmor/weapons.h tml wrote:
Masterwork Weapons
A masterwork weapon is a finely crafted version of a normal weapon. Wielding it provides a +1 enhancement bonus on attack rolls.
Without using magic, you can't add the masterwork quality to a weapon after it is created; it must be crafted as a masterwork weapon (see the Craft skill). The masterwork transformation spell transforms a non-masterwork weapon into a masterwork weapon.
The masterwork quality adds 300 gp to the cost of a normal weapon (or 6 gp to the cost of a single unit of ammunition). Adding the masterwork quality to a double weapon costs twice the normal increase (+600 gp).
Masterwork ammunition is damaged (and effectively destroyed) when used. The enhancement bonus of masterwork ammunition does not stack with any enhancement bonus of the projectile weapon firing it.
All magic weapons are automatically considered to be of masterwork quality. The enhancement bonus granted by the masterwork quality doesn't stack with the enhancement bonus provided by the weapon's magic.
Even though some types of armor and shields can be used as weapons, you can't create a masterwork version of such an item that confers an enhancement bonus on attack rolls. Instead, masterwork armor and shields have lessened armor check penalties.
So shouldn't all that is needed be for the characters unarmed strike weapon to have been created with a sufficiently high craft check and 100g more in raw materials (beyond 0)? I ask because I am in a multi-generational game atm, on the second generation, and one of the first generation characters was a human perfectionist, and primarily a crafter. They wanted to implement eugenics, and institute policies to make sure the children born are the best they can be, and went as far as to expend over a million gold throughout their adventuring career and after to establish schools and other facilities to do so, and yes, they had something like a +30 to their craft checks, for whatever would be relevant.
Essentially given this context, is there any rules reason for said children to not be able to be enhanced as magic items, or anything that would prevent their unarmed strikes from being masterwork weapons?