Well, the engine history makes it very hard to value but I'd guess probably less than this: Redbay 6.5 optimax 200
which has presumably just sold for a bit under £13.5k. It might not have the most popular tube colour, and is a meter shorter slightly smaller engine - but its newer and the engine hasn't been for a swim.
And this is also smaller, with only 150 horses (but low hours, still in warranty and no scary history) but is going to appeal to similar buyers to yours - for similar money to the one above and much newer Tornado 6.5m Offshore Rib
So I'd guess if you are looking for a quick sale it has to be in the magic sub £10k range? So its competing favourably with this sort of thing:
2001 Humber Destroyer 6.1 + Opti 150+ Trailer Package
at £9.5k obviously that is a different kettle of fish - but it all depends how buyers view the engine history. Or something a bit closer to yours which has now sold but was advertised here as "Tornado 6.6m (mid 90s) 150hp Optimax (2001, 700hrs) £7,250 ono. Trailer. All excellent condition.