This Mercedes was just featured on BaT and is currently for sale on ebay for 12 grand. While I think the price is way too high for a car with tacky wheels, ugly bumpers and a 4 speed slushbox, the idea is as awesome as it gets.
The W123 was nearly undestroyable and offered huge amount of space. It even had a super cool 7-seater option with a folding third seat row. But it never was fun or powerful. With a swapped in LS this car gets close to what I imagine a 6.3 SEL Wagon would feel like. But I'm a engine swap lover anyway, so probably I am biased.