Oil leak help/price?

Hi all, now before i start i know land rovers all leak oil lol. But this leak is bugging me and leaving its mark everywhere!
First of all i thought it was the sump gasket so re-sealed the sump gasket. Now its still leaking the same place. Appears to be from front of engine at sump gasket but im starting to think it may be the timing chest.
How much would i be looking at for timing chest to be sealed and obviously timing belt done as well. If anyone fancys giving me a price for the work im in basildon essex.
Thanks all

Sorry should mention its a 300tdi discovery. 1995

Most likley the front crank seal.

Well ive got home today, taken my wading bung out and theres a little bit of oil there but i cleaned everything off and run it up and watched it and can see oil leaking from what seems to be the timing chest at the bottom above the sump.then runs down onto the sump.I think its leaking at the bottom as i cant see it running down from anywhere. So i think it may be crank seal and timing chest.