If I couldn't find what I need I'd make it when feasible and for bushings or mounting insulators I'd try spring end pads for semi trailer suspension. They come in a number of sizes and thicknesses and have to be durable for what they're made for.
To give a visual idea of what they are...
http://www.nickstruckparts.com/325-151.htmlhttp://www.nickstruckparts.com/palocu.html#paginghttps://www.google.com/search?q=fruehau ... kgodUMQFLAWhen a round one is needed a hole saw is what I'd use,then drill the center hole to the size. A drill press would be best if there is one.
These are holes saws in case anyone is unfamiliar with them;
https://www.google.com/search?q=hole+sa ... kgodGuQHVQThis mfr. makes the above and many,many other bushings mostly for big trucks and trailers,the PDF catalog has measurements for many so might be worth looking at. It also lists mfr. & competitor pn's.
http://www.durothane.com/
12 yrs.exp. in IH dealer parts dept.
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