The estimates for an item that you can use "at will" to do repair 1D8+1 damage is just 2000gp. (1x1x2000) Alternatively the mending cantrip that heals 1 damage is gettable for half that. Useless in combat, but when the fight is done you can just take HP rounds to get back to full.
If you took a single level of artificer or wizard you wouldn't even need to do UMD checks, plus as an artificer you could cast a bunch of infusions on yourself that may come in handy.
Alternatively a twice a day eberron's eternal wand may suffice.