Take the two screws out of the needleplate and the bobbin holder will pop out. Just be careful to line the top finger into the notch in the plate when you put it back together. sew-classic should have a bobbin case and also has a free download of a manual with better directions on removing the bobbin holder. Good oiling and greasing directions, too. This one needs grease. It looks like you need part of the bobbin winder, too. I think some members here have some donor machines.
It will be a great machine to sew on when you get it together.