Thanks for the info, Moutere.
I found some of those Coleman containers - new - in an 'outdoors' shop today. However, at the price of them, I doubt that too many people would be just using them a couple of times and then chucking them out in the recycling.
Not sure how easy or otherwise it would be to attach paddles inside them with water-tight fastenings. (I'm looking at making a 'wet' tumbler) But I'll keep them in mind.
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