I have a couple of the older Weaver bases, I think they are a 92 and not 92A, that were made in the 70's-80's, that were made for octagon barrels. The front of the base was relieved back to the screws, making a nice looking base, but I think it would weaken the base. I would only use it on a easy shooting round.
You might find one on some of the forums classified or maybe Ebay.
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