I would guesstimate the value at $25 if in need of service maybe $50 if sewing. If the idea is to resell on Craigslist you can start at $100-$200 and see what the market will bear. These White machines are good sewing machines but not particularly valuable like a Singer Featherweight or others.
Vintage and antique sewing machines are for the most part very much undervalued. Your $5 White would cost $1000's if made new today. So you have a tremendous value but it is known to only a small group of scattered people who are used to paying little for high quality sewing machines.
Good Luck
Jon