I use blogpatrol.com to track visitors and popular topics to my blog. It is free and I find it very useful. Tonight I see that someone found my blog by searching for "sewing machine used by Christine Jonson". I happen to know that answer, and it is not already written here in the posts.
Christine uses a (*drum roll please*) Pfaff 1222 E! I looked here for a picture of hers, but the one that shows up is not the original one. She has a beautiful all metal body 1222 E. She does have another that looks like these, but she bought it later as an extra shop machine.
An important feature is the dual feed. I was sold on it after using Christine's machine and I couldn't find a used 1222 E or another used Pfaff at that time (I think it was about 1995). It was before the internet became so useful! I bought a new one. It was the cheapest Pfaff I could get at the time with dual feed. And I suspect the shopkeeper gave me a deal. I paid $600.00, it was worth every penny and was the most I could afford at the time. I still have it accessible, have used it very heavily (it has a thread mark!) and it still runs like a dream. It handles all types of fabrics expertly. I just used it this week because my industrial Pfaff 563 wouldn't sew vinyl.
My Pfaff Varimatic 6091.
Holy cats! You can still get one!
I encourage anyone who has a similar question for Christine to ask her! I'm sure she would answer your questions in good spirit :)
edit November 28,2013**The Pfaff 6091 doesn't seem to be available anymore at the link (I recommend stalking your local craigslist.org, they do show up from time to time in excellent condition, be sure it has the dual feed), but here is a link to bobbins for the older Pfaff models
Pfaff 93-040970-45, PD60 9033P Pack of 25 Empty Plastic Rotary Bobbins 130-362 808-955 1006-1475 2010-2040 6085-7570+ later Sewing Embroidery Machines