Depending on where you sell it ,id say if you email uk companies you can probably get 300 -400 us ,a lot of companies using the keyword, I myself would put it buy it now facebook for 300 bucks and just email a bunch of endusers the ebay auction
yes instead wales travel is probably limited to companies that book travel in wales,instead try and find names like example world travel or global travel,that have massive companies using the keywords ,with this amount of end users you can even market other extensions