they were a quid for 25 750ml ones and 25 1.5ltr ones in a box. the smaller ones fit nicely inside the bigger ones too. (im not affiliated with ikea)(my mum might as well be though)
Nice machine, you can date them pretty accurately by looking up the serial number on Singer's website
... a box that might become a wannigan with a little work. Well, I had to justify the trip somehow
Sounds interesting, got a model number or picture?
Oh, and congrats on your 6,000 post