I put a N.O.S. 3t (ttt) Pro Chrome Corsa quill stem on my RS-22, and the ovalized TIG'd extension provides considerably more stiffness than either the 1A on my Paramount or the Nitto Technomic I had on the RS-22 before buying the Pro Chrome. They're fabricated from Columbus Thron chromoly tubing and available N.O.S. on eBay in various extension lengths.
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