Help!What to do?Storage damage at Fiesta 1.3!

Hello, I am here for the first time in the forum and absolutely need an independent opinion of you, because somehow you can not trust the workshops! So three days ago the camp damage occurred with me suddenly on the highway, I was towed and now my beloved Fiesta just stands around! I have a Fiesta Chianti 1.3 from year 1994! I drive the car now are three years and am happy with it! he has run 105000 km and is a highway vehicle!! ! The harm hit me very much! Now I don’t know exactly what to do? I was told that a reperature is hardly possible, why I don’t know or it’s not worth it. I can turn on the engine normally only there is a knock! I have probably always refilled too carelessly oil which probably caused the damage (lecture for life! In some workshops new or used engines are offered to me in the price range of 400 to 800 euros! They say it is very much on What can I do now??? Don’t give me a chance to repair or replace such a warehouse?Price? Or is it not worth it? Or rather a used engine in?What is better??? I ask for professional advice !!! Thank you in advance!!!!