Please clarify your weight numbers; I think 1200's and/or 1500# is a tall order.
City, highway, or combo?
Looking at your list I think of the Opel GT.
New Project 69' Opel GT 1.1L - GasSavers.org - Helping You Save at the Pump Hypermiling and Fuel Efficiency Forum
I know a local that has MGB GT's for sale.