There are 3 homes in a current Prattsburgh search for sale for $56,900 to $99,900 that appear to fit your criteria. The listings do not "officially" define them as double-wides, but they appear to be that or similar.
Feel free to give me a call here locally at 315-532-4726.
Your profile says home seller. So gathering that you are thinking of putting your home on the market.
The best person to give you an estimate of Fair Market Value is a professional who know three things:
1. The local market and values
2. Your property
3. Your personal situation
Even with the best of intentions offering a valuation from Trulia posters would be a guess at best.