Chris makes a good point. Brad Hawpe is better than Jeff Francoeur and totally available. Hawpe’s not a good fielder but he can hit a bit. Here’s the thing, though, if the Mets wanted to find a better-hitting right fielder than Francoeur, they could try just about anyone.
Tedquarters
Ted Berg
Tedquarters 
look, the mets are out of the race (for all practical purposes). at least to the extent that “upgrading” from francouer to hawpe is not likely to key the miracle comeback run.
So, instead of bringing in (and paying for) a 1 month rental (I am assuming he will be a FA after the season? Or at least an overpriced arbitration guy like Frency), go internal.
THey have a couple of OFs raking at AAA that can “hit a little” most likely, and don’t play GG caliber defense.
Just call up Evans and Duda, and let them platoon. Or just Duda, and play him everyday, to see what you might have.
they canl also play LF (both have more time there than RF), with pagan covering right, better than Frenchy does (defensively too).