I'd put on the 3 blade. Hartzell do a Top Prop conversion for the 182.....For our Commander, ours cost ~£7500 inc VAT delivered via Proptech in portsmouth. The same TopProp from the USA was about $10500 + shipping + VAT so it was cheaper to get it in the UK. Gives about 3 inches better ground clearance, and looks much better and the scimitar blades are meant to be quieter.
I'd get a new prop, no question. The shock load test for insurance purposes will probably be 5 grand, and a rebuild say 20,000. If you could offset the 5k against the 20k then it might be worth considering a zero times overhaul at NMA? But iif the engine is ok, then I suppose you have spent an extra 15k for nothing....?