This is an interesting request. $5000 is good money for a Buffalo Boat. The BB is a relatively small and very quick and simple boat to build. However Paul (Pee Kay) above has requested the boat to be a bit longer than standard. That's not an easy request. That's boat design work. That's not so easily done. As such his proposed boat would end up being a lot like the infamous Peter Mac Pram. Peter no longer builds boats so you can't get that boat directly. I get a dozen requests for information about it every year.
I might even put some panels together so I could work out the dimensions for the plans, but not actually build the boat. I'd make those available to anyone who wanted to build Paul's "longer than normal" Buffalo Boat.
Jason Cajune makes a hotrod pram too. I doubt you'd get one of those for as little as $5000 though.