The seller is going to try and find the paperwork that he has for it, but I doubt he has the New Vehicle Information Statement, or the original bill of sale.
I once bought an 07 WR250F from a guy who moved to Ontario from B.C. His bill of sale was not enough and I had to fill out some kind of form and then get a bill of sale from the previous owner who was the original purchaser in B.C. It was a big hassle but I eventually did get Green Plate registration for it.