Pete...
Wow what a great find. This is a 1980-81 model. It still used a metal height adjuster that was later made in plastic. This model was near the bottom of the line. I just found one this summer and recently gave it away to someone who needed a good vacuum (she has dogs and small kids).
The bag is very common and used extensively throughout the 80's. I would check with a vac shop as they may have an NOS one or a nice used one. I do not have one at the moment. I do have a few used BOJACK bags, but they do not look as nice. If you can live with a broken zipper, you can easily fix the bag holder. Just remove the existing plastic holder and put in a wooden dowel rod. Just cut the rod to fit and voila, the bag will hang straight. The zipper can be held with safety pins until you can find a replacement.
The paint on the hood is easy to remove with a little Brasso. I too find paint splashed on a good many of my "finds". I think that when people go to paint, they use the vacuum first then it sets out in anticipation of cleaning up afterwards. In the process, it gets paint spilled on it.
Thanks for sharing the pic of your newest find...CONGRATS!
When you get her all cleaned up...post a pic. I would love to see her all shined up!
--Tom