I just bought this same model for the same price, but with a cabinet. $30 alone is still a good price. Aside from the top gear that's plastic and can fail, these machines run forever and are heavy duty enough to handle denim

Edit: just want to say that old, pre 80's, Singers are the ones that run forever. Newer ones have a bad reputation for going to shit quickly. I believe the one you have is late 60's early 70's