Hi there Ceres
The guy on Ebay selling these plans is also selling photocopies of the Swordsman plan which belong to FLJ on this Forum. There are also one or two other plans of shall we say dubious nature. But, the plans for the vessel which you are interested in, look to me as though they have come from a book - such as Model Shipwright - and they may have been enlarged. I can only make out one or two frame drawings but no doubt you could if you tried hard enough build a reasonable model from these plans.
Before you part with cash, have a look around different websites & different magazines for the plan publishers - because I bet to get the original plans, it will not be much more expensive.
aye
john e
bluebird