Don't imagine it'll help in any way, but Gunparts Stateside list 'em at $4.30US each. $5.50AUD. Plus $4.95US shipping, I think. No mention of heights.
Might be worth an e-mail. 'ET' is Eastern Time. Yesterday to you, I think.
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You could try Western Gun Parts here in Canada too. They have no on-line catalogue though. Might be less government interference.
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