Think my cam belt has gone which has completely mashed my engine, the mechanic said that it looked like the valve had smashed into the head and to fix it would be at least £1000+!

I had a quick look on ebay at a few engines and they didn't seem too expensive, and my dad seems to think he could fit it.
So basically i need a new engine for my Megane 1.6 2003 Dynamique, i was just wondering what engines can i use? Would the engine have to specific to another 2003 1.6 Megane or could i use an engine from a newer Megane or even a 1.6 clio etc?
Any Advice would be massively appreciated as i am looking at a huge bill and need to work out my options.
Thanks in advance
Sam
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