Ok so I guess a semi scale type about 36"? As you don't have lots of building time would you not be better looking for a ready built model as even a kit build is going to take several months and you will need to source motors and running gear.
There are many suppliers on the web and a quick search has revealed in alphabetical order
There are more but this may help with your search.
If you type Model Boats for Sale using Google you will see a good selection of models that fit your requirements. It will be based on your location, London?
If you do consider this option be aware that wooden hulls can and do leak so I would stick with a plastic or F/glass hull.