cost for a racial-specific charisma item?

[foobar1969]

I'm imagining a wearable magic item that grants an enhancement bonus to charisma, but only to a specific target audience. For example, a laurel wreath that affects natural creatures (e.g. wild empathy) and the fey.

Does something like this already exist? If not, would it be fair to price a +4 specialized item as equivalent to a generic +2 enhancer?

[Andion Isurand]

Per the sidebar Behind the Curtain: Magic Item Gold Piece Values (DMG pg. 282), if the item requires a specific skill to use, its cost is reduced by 10%; if the item requires a specific class or alignment to use, its cost is reduced by 30%.

A race-restricted discount should probably be at least the same as a class or alignment discount, since its harder to change race than it is to bend to meet a class or alignment requirement.

However, I'm not sure what an "applicable target" restriction would get for a discount.

[JyP]

I'm imagining a wearable magic item that grants an enhancement bonus to charisma, but only to a specific target audience. For example, a laurel wreath that affects natural creatures (e.g. wild empathy) and the fey.

Does something like this already exist? If not, would it be fair to price a +4 specialized item as equivalent to a generic +2 enhancer?
There's the Belt of Dwarvenkind (http://www.d20srd.org/srd/magicItems/wondrousItems.htm#beltofDwarvenkind) which can be used as a template there - it does a lot more than a bonus to Charisma, but for a surprising low cost.