The Parts Place Inc out of Chicago sells what they claim to be the non water based trunk paint in Black & Gray or Black & Aqua:
Their current eBay auction: http://tinyurl.com/244umn2
(end's in 6 days from 4/25/11)

We now have the correct formula trunk paint used by the OEM manufacturers when the cars were made. The paint is sold by the quart. There is more than enough to do several trunks floor and sides with this quart. Paint must be applied by a primer gun or one of the cheap Taiwan paint guns. You will NOT need to clear coat like most all other trunk splatter paints on the market. Lies out like the factory concours quality and comes complete with directions. This is a petroleum based product like no other on the market.

I hope to give this product a try on my trunk... maybe this summer? But I don't know anyone personally who has tried it yet...

Brett!