I was going to suggest the rod and orb, but they come with a warning. They cure ability damage (ie temp), but not ability drain (ie perm). Restoration cures all ability damage, and the ability drain for 1 stat. Restoration also dispels negative levels and restores 1 lost level. The rod and orb may or may not work, depending on what the OP wants the restoration spell for.
Ring of Spell Storing (DMG) - pricey, and you need a caster to put the spell into the ring in the first place.
Potion - normally potions are restricted to 3rd level or less spells, Restoraton is 4th level and so can't be put into a potion. However, there's at least 2 classes that CAN put up to 9th level spells into potions. And if all you need is Lesser Restoration, that can be put into a potion by any old potion maker.
I think there's a Scarab in the DMG that stops you from taking ability damage/drain and negative levels in the first place.
Good luck!
