I've just taken delivery of a purchase from eBay (£11).
First the bad news
I knew that this would be the case, and anyway the lens is an SMC Takumar 55/2 and since I already have an SMC Tak 55/1.8 I don't mind junking this lens. The infection is very thorough, when on the camera the view was very foggy.
Now the good news.
Spotmatic SP1000. There appears to be a bit of damage around the viewfinder where it looks like the camera was probably put down on a rock and hence scratched the paint work. But other than that, the mechanics are fine: wind-on works, mirror moves correctly and returns, and there is no sign of corrosion in the battery compartment. (I've got a hand held light meter, so I am not sure if I should bother adapting it to use a silver oxide battery.) There's no obviously pealing seals, which either means there aren't any, or everything is fine.
Since the camera came with a leather case I guess I have all I need to run a roll of film through it, other than the film! (I'll have to remember to get some when I am next near my local camera shop.)