Due, sounds like you have the fresh water issue more than adequately addressed.
Of course, you've already considered a completely mechanical pump for your well - of the type that windmills and oil wells use. A very small pump jack like what is used on oil wells, would be an 'interesting' addition - and quite functional. Those pumps are pretty durn good. Used to sell 'pump leathers' for windmill pumps way back when (high school - working at Big Spring Hardware). Have only been involved once in my life in 'pulling' the tubing from a water well. Think it was around 20 joints or so (so maybe close to the same depth as yours. Involved a portable A-frame - and jerry rigging for 'holding' the pipe in place (to prevent dropping) each time we lifted and unscrewed a joint. Was a real blast to do it.
On drilling rigs - several 'trips' a day are sometimes done when shallow - can take 8-12 hours to 'trip' the well when the depths get to 10k+. And yes - sometimes the drill string gets dropped - and life suddenly gets very interesting (and expensive). Fishing the hard way. *s*
A pump jack can be electric powered, gas powered, or 'human powered' - say via chain and sprocket assemblies.
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