mate near enough the same thing happened to me, my escort had only 63k at the time for a mk5, tensioner pulley shattered into 4 bits, when i took the head off, first glance was 8valves had bent, but whilst lapping the other 8 back i found the marks showing the other 8 valves had bent ever so slightly, all in all it cost me just over 350 quid, bearing in mind i built it all meself, id say build it up again mate, and happy driving, you wont need a new engine as the pistons are relatively hard compared to the valves