Howdy,
The 07 series saws was one of Stihl's most reliable and tough units ever. The old upright design, however is about the ultimate ugly duck. Stihl has been trying to discontiue it for years. They last used it as a powerhead for a cut-off (abrasive) saw. I believe the unit was around from the '60's late, through the '80's. There was a slightly larger version of this unit, the 08.
The handle placement on these made them difficult to control in a kickback situation, which was another big reason the manufacture wanted to see them go by the boards after the industry safety push in the very late '70's.
I don't have specs on the unit, as this sort of thing as about the last thing of any interest to me. It either cuts well or doesn't, and it's useful life to be expected - are far more important in my world. Anything else can be solved with proper applicaiton of a good file.
As for parts, I would imagine that new parts should be getting durn difficult to get. There were a lot of these around however, so going fishing in a large dealer's junkbox could be productive.
Regards,
Walt Galer