So this thing is a ProForm 390pi power incline.
It is in good shape as far as I know. Supposedly run $600 new (but this one was bought closer to 10 years ago). My elderly father walked 20" daily on it at about 2 mph for 6-7 years, but not in the last three.
Here is a brief review of it
About The Proform 390pi Treadmill | LIVESTRONG.COM
Parts are still available.