Cost to replace engine with used one with 85,000 miles is $ 5,100.00 seemed high for used. Is that a fair price?

What is your question?

The timing belt broke sending the Pistons thru the engine. It was inspected by the extended warranty company we have and they agreed it had to be replaced. They pay 3,500 leaving us to cover the rest so can someone help us know if 5,100 is a fair deal? Thank u.