I am in a similar situation just now.
Bought a bashguard with bolts, two of the four bolts are stripped, not all the way, they tighten up without bashguard, but with bashguard on they can't bite.
A new set it 6.99, what I paid of the bashguard in the first place.
Contacted seller on Friday, will give him until Monday to respond.
Quite happy with 3.50 paid towards the bolts, but the full 7 quid, I could have bought a new one for that.