currently the game doesn’t support a “damaged” item, it supports a seprate “damaged” item that can’t be repaired, but that’d be something that would have to be decided on.
A “fix” I might do instead is give x number of kevlar/ceramic/etc plates that’s not enough to “repair” the vest along with an empty MBRV (Since in theory it’s just a vest with big pockets)
Assuming Skyrim, Planetside 2, or other games doesn’t eat all my off-time.