Engine sounding rough?

What could this be? Its an astra 2.2 Sri with 27000 miles on a reconditioned engine [iMCLpZYvm4k[/media]]
https://www.youtube.com/watch?v=iMCLpZYvm4k
]([media=youtube)

Sound like a bottom end going out and loose chain, for me

it doesn't sound too bad in that video, possibly an air leak half way through and at the end the big ends sound bit noisy notsure.gif

Bottom end how much roughly is that to get fixed or the timing chain? :o