I need them for a rare exhibition at the university. Our theme - where did your playing life begin?
It depends on what you mean by "first versions".
Well, the first game that featured Mario was Donkey Kong in 1981 as an arcade game. On the old Game and Watch system, there were several Mario games (these are extremely rare and no one is going to just hand them out to you) but the first NES game to feature him as the main character was Mario Bros I believe. You can buy the NES cartridges on Amazon.
Don't forget there are SNES and Gameboy games as well.