My guess is that very few teams would be willing to part with robots forever... (there is some sort of weird family like attachment that grows the the hunk of metal that you spend every waking hour of six full weeks of your life with) however, I would guess that there are MANY veteran teams that would be willing to lend you one of their old robots for the season.
229 gave us one of their old prototypes, and several of the rochester teams have been very generous at lending or demoing robots for us... so I would suggest you try to borrow a bot for the season
