Hi 2F. I'm always willing to rescue a very-old-camera... well, if it's free or less than $5. I have several Brownie box cameras kicking around, and love them too. I love that something cardboard can work after 100 years. I believe I have a No. 2, like you, that takes 120 film, but it's missing a winding knob, I think. Easy enough to patch up, but it hasn't gotten itself on the project table yet. I do have a scan of a photo I took with a very similar Brownie box camera (the No. 0) that's a little smaller and takes 127 film. I'll post it to this group.
The long formats of some of those old cameras are spectacular. I have an old Folding Hawkeye that takes 6x9 on 120. It's a great size.
You can find a scan of the manual for your No 2
here
You can find a photo of the original box this camera came in
here
(You can also waste hours on both of these websites learning about old cameras!)
Try a bit of gaffers tape over the red window (just peak under it quickly when you're winding). The spring sounds like an easy fix with tape and some bit of something (bent paper clips?). But like Akki says, these cameras are also kind of a dime a dozen, so you might also want to just look for another and/or use one or the other for parts.
Have fun!
annie (aka cordelia)