Need Aluminum plug inside carb '80 gs550

[crazy5]

That is because they are not part of "normal maintenance".

Those o-rings are actually a square-section ring, and are only there as spacers to keep that aluminum plug in place.
In normal use, there is no "wear and tear" on them, so they don't need to be replaced, unless you lose them.

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Exactly. I didn't mean that as a criticism of the cycleorings.com kit, in fact I was thrilled with the quality and completeness of it. I just wanted people to know where to find that funky square-ring if they lose it.