The originals can be found, still dry, with the original casel. I think I have one or two in my shop.

If you get an original, be aware that back in the day of 6 volt batteries, the battery acid used was stronger, 1.280 SG. The stuff you get at the auto store is weaker, 1.265 or thereabouts. To get full charge and get the last (green) ball on the charge indicator to come up, you will have to find some concentrated sulfuric acid and add a bit to the auto store stuff until it indicates 1.280 on a battery acid tester. Always add the concentrated sulfuric to the weak stuff, never the other way around - intense splashing. Once it is charged,you will have to keep it on a trickle charger or it will go flat and sulphate. One of the little 6v power packs for portable appliances will suffice.
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