If I Mirror Image a unit with an Equip, does it get the Might as well?

No, a Mirror Image copy does not get the Might from the equipped Gear.

According to the RiftJudge FAQ (#10239, #9410), when you create a copy using Mirror Image, the resulting Reflection token only copies the unit's "copyable traits," which are its base characteristics (printed Might and Rules Text).

Anything appended or granted to the original unit—such as Buffs or attached Equipment (Gear)—is not a copyable trait and is not inherited by the token. Therefore, the Reflection will not have the Gear attached to it, nor will it receive the Might bonus that Gear provided to the original unit.