Here's a report on the destruction of Haiti's cultural heritage and many Haitian paintings, including the supreme achievement of Haitian art, the murals in the Episcopalian cathedral. Furthermore the "Nader Museum" in Petitionville has largely been destroyed; that was probably the single best collection of Haitian art.
OK, so the supply curve shifts up and to the left. But will the prices of the remaining stock rise? It's not so simple and that's because of how reputation drives art prices. In part people buy art to be affiliated with something grand and glorious. A so-so Rembrandt is worth more because the first-rate Rembrandts exist. If the first-rate Rembrandts were destroyed, the so-so work might fall in value, not rise.
Art works also require buyers to promote them. If not many people own an artist, not many people are speaking up for that artist. Again, we see the higher quantities can increase rather than decrease price. Arguably Andy Warhol's prices have benefited from Warhol's work being widely held and sold in deep, liquid markets.
If you are curious to see some of the Cowen Haitian art collection, go through my home page. (Addendum: Links are broken right now, I'm working on getting them fixed.)
This account of the damage also offers a good slideshow on Haitian art.
What about the data? Natasha and I have bought four Haitian art pieces since the earthquake. Their prices were exactly the same as what we had been quoted before the quake. So far the jury is still out.