RC,
You're probably right, or maybe after all their expenditures on the gun, carriage, and outfits they have to save for a little while before they can afford a proper oak bucket. I got curious, so I went googlin', there are Amish made pine buckets that go for around thirty, but they're described as decorative, this one is definitely utilitarian. It seems a little high to me, but I'll defer to your judgement if this is a fair price, or not.
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Cannon Bucket
In the days before cannons were breech loaded (i.e. loaded from the back), a cannon would have to be "swabbed out" between firings with a rag or sponge on a stick dipped in water, and this bucket is what the "swab" would have been dipped into. Our Cannon Bucket is built with a locking lid securely tied to bent steel handles made by hand on our forge. Height: 9", Diameter: 8.75" top, 9.5" bottom.
Price...$400.00