Just to make it easier for folks to find the picture and answer the question.

Laszlo

   I don't know anything about that particular camp chair but the logo is GCI Outdoor. REI carries that brand. 

   The store bought seat pictured above and all similar purchasable things will certainly work.  But if you'd like a very functional touch of class, that comes with quite a bit of work, consider what I made, pictured below. Very classy touch, if you ask me.  :)  It is hinged and folds down such that one can easily sit on top of the back when folded down.  Not obvious from the picture, but the horizontal slat is mitered into the vertical slats, so the seat back is flat when folded down, making a smooth seat.  There is a line attached to tie the seat back to an eyelet on the stern to make sure it stays secure while raised, and you can see the cleat that allows that same line to "lock" the seat in the down position for trailering or if worried about it during really rough sailing conditions, etc.  My wife calls it her princess seat, and uses a thin neoprene seat pad under her bottom for padding, and to prevent slipping about.  The pad does have to be moved prior to folding down, but then can go right back in place to sit on top of the seatback when folded down.  BTW, the tiller extension is another custom item, made of a rattan pole.  Very functional and nearly unbreakable.  And the tiller itself is an oak dowell, it goes through a hole in a modified rudder head (and is thus removable), making tiller, extension and rudder storage much nicer and compact..

   I forgot to add that the side-lines that support the seat back are tied with taught line hitches, making the angle of the seat back infinitely adjustable to personal preference.

   Nice bit of work there but I'm looking for something simple