here is a page I found a while back from a wave spin but the rigging is similiar on a 16 or tiger for that matter.
http://static.hobiecat.com/2010_archive/support/pdfs/spinnakers.pdf
if you want to go for used sails, any skiff or cat asym spin will do. draw a sketch of the boat from the side and figure out your dimensions for luff, leach and foot then go hunting for sails. you want a spin from another fast boat cause the sail is cut flatter. look into the international 14 skiffs too, not sure about the size on that one but there is a decent fleet of them, I think the 49er would be too big unless you want to go for a masthead spin(chance of breaking the mast with that) if you get a hold of a sail cheap you can get it cut down at your local sail loft, won't be perfect but I presume this is for blasting past everybody else on the water and not racing.