You might also try www.thorlabs.com who produce opto-mechanical parts which can be used to build stuff - using 1/4" x 20tpi which fits tripod threads, or M6 - some of their parts could be used if you like mechano! I use them for all sorts of things - they manufacture in stainless steel and anodised aluminium.
As an example: https://www.thorlabs...ectgroup_id=223
Not cheap but probably cheaper than getting stuff machined unless you diy.
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