Remi, the ad states "Head was port matched and polished exhaust. combustion chambers were enlarged to reduce compression and to facilitate polishing."
The motor is a long block, does not include the manifolds. So 1st thing you'll need to know is ported to which manifolds, Renix or HO.
50K miles. Not outrageous, but you'd need to know who the builder was, i.e. the seller, Titan, Hesco, etc.? The only stroker I'd trust @ 50K miles is a Hesco.
What was it used for: full time crawler, driver, or in between?
Ask if the seller's name (or previous owner) is Kyung. Seriously. He was selling his Hesco stroker awhile back in the same Cali AO. If it was his engine, it's good deal. It was a $4K+ crate special engine.