I have a twin to that machine. They have their quirks but are a nice machine. Those were early decorative stitch machines - the disks are still available. Here is a free repair manual:
http://parts.singerco.com/IPsvcManuals/306W25.pdf Have some fun - see if you can get it to work. Sew Classic has bobbins, needles and attachments
Here is a link about a 319 - it is very much like your machine but it has additional keys to change the stitches - otherwise it is the same.
http://www.quiltingboard.com/picture...c-t162425.html I had a lot of work to do on it to make mine work - I did it with everyone's help. It works fine now.