Even if that machine gleamed like a 10K diamond, it wouldn't sell for a hundred bucks in my far north US neck of the woods. The cabinet has been nicely stripped and appears ready for a finish. If the repair work is done to the sagging area, someone might give $50 for it to make a night stand out of it. The cabinet will never be original again, no matter how nice it looks.
In an urban area, it could well be a different story. But I watch my local classifieds like a hawk and I can tell you, nobody wants old treadle machines. They go for $25 to $50, almost regardless of condition. About a year ago there was a gorgeous Davis Underfeed. It shined like new and the lady couldn't get a hundred bucks for it.