Boy, he doesn't ask for much, does he? Tell him you'll put the same amount of money it will cost you for a new puppy toward "ONE" of those things (the Gibson might be easier to find). Anyway, if he is willing to make a deal, he isn't against you having a puppy. Find your puppy and then tell him you'll help look for the thing he chooses. You sure can't blame the guy for trying! My husband just got a brand new quad with hydraulics and a plow for it for quitting smoking. Now that deal was worth every penny of it. Not smoking is paying for the quad!
Wait....I just reread what you wrote, maybe the car will be easier to find!