So what size is this buddy of yours and what kind of bike interests him? If he's 6'6", he's going to have trouble fitting on an SV650, but something like a used Honda XR650L might be more in line. If he's more into cruiser bikes, then he's pretty much limited to japanese stuff with that budget you posted.
And speaking of Honda CB750s,
here's a CB750F Super Sport posted a few days ago on the San Diego Craigslist. That's a good place to scout around for possible bikes. You can also expand the search up into LA since he has a good buddy like you to ride it back to San Diego for him, right?
