i'm on the look out for a good-working treadle- with a $100 budget- so will look until the right machine comes along-
the value of any vintage machine is really what you are willing to pay for one.
some people will pay $500+ for one- some people will pay $25 for one- it's all relative.
my little 1956 singer i see on ebay going to anywhere from $100---on up to $250+...i paid $20 for mine- and love it!
it all just depends on your budget- your desire- what you are willing to pay.