Just got this in from eBay. I couldn't make out the stamp from the seller's photo, but I thought I would give it a go because my RAD is extremely vulnerable to dip-at-the-toe stubbys. Upon examination, it still leaves me in the dark. It says LISBON but the stamp is stacked as shown. Anyone ever seen this stamp before? I don't think it is a Warburton of any sort, but who it could be, I can't find.
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