Hello Ceci,
Perhaps it is hiding, but I can't see the tension spring - the little wire hook that should be beside the tension discs. If it is missing you can get one from Treadle Lady
http://treadlelady.com/Treadlelady.com/For_Sale.html
If you want to pay a few quid you can get a shuttle from Helen Howes
http://www.helenhowes-sewingmachines.co.uk/bobbins.html
Why is the needle plate so mucky compared to the front and back slide plates? I hope it cleans up to match.
All in all it is a smart machine and looks as though it should be a good runner.