Welcome to the forum. It looks like the bushing is standard and I suspect that answer you're looking for may best be answered by Leigh themselves. If you're referring to router base then there are many universal bases that may fit or can be drilled to accept your router. For that matter you may be able to fashion you yourself by tracing out the existing base and hole pattern. Here's a link that may hold some clues, https://www.highlandwoodworking.com/leigh-guide-bushing.aspx
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