Sorry that I don't have one I can recommend without reservation.
A friend at work swears by the late '80's Mercedes 300 diesels. If your brother in law owns a restaurant chain you're set for fuel.
I'm pretty sure the Camry and Accord wagons runs ended in the mid '90's. If that's correct you'll find fewer and fewer of them available in good serviceable condition.
Saturns: probably the longest run of FE wagons, in terms of how recently they were made (well, maybe a tie with the Escort). Not too hard to find, and gently priced. Saturns are known oil burners, readily acknowledged on the Saturn message boards such as
SaturnFans Forums - Powered by vBulletin. However an Auto-RX treatment might clean up the oil burning. I have no experience with Auto-RX yet but ordered some today for my Civic. Saturns have another issue in that we're not certain if the dealer network will remain alive etc. etc.
Escort: Probably not quite as roomy as a Saturn wagon but better FE. Dealer network seems more likely to exist into the future, at least from the way things look right now.