sirgallivant said.. Google 'Dido's watermaker'.
Now look what you have done
sirgallivant 
opened up possibilities
I'm sure at one stage I checked out small pressure washers and was told by a person that one brand maybe not K archer have at least ceramic pistons
http://www.albin25.eu/our-a25ak-dido/34-dido-stories/60-didos-watermaker?start=2 Next year for me but Ill start sorting parts
