I think the Redbook "unpriced" listing is a little misleading. We're used to seeing that when there's a one-of-a-kind extremely rare jar, not offered for sale, so we have no idea what it may go for. These are modern and much more plentiful. While us fruit jar collectors don't have much interest in Longaberger jars, they seem to be wildly popular with the Longaberger collectors. Just search eBay for "Longaberger jar" For a more realistic feel, search sold listings only. As far as canning with them, why pay some inflated price when I can go to my corner grocery and get a dozen canning jars for $8 - $10?
Jars must be cheap on the left coast, heck a dozen canning jars at wally world down here are 13 - 15 bucks! we pick up ours at garage sales for 10 - 25 cents each! [][][][]
I believe that longaberger jar was part of a set that came with a basket. I think there were 3 of them that set in a basket to make the set. I see them a lot for 5-10 each here in southern ohio at flea markets and such