Keihin CVB36 float bowl oring size

If this has already been covered and is archived, please post a link - I've searched and come up short.

I'd like to replace the float bowl o-rings for the keihin CVB36 carbs off my 75 kz400d. Replacement o-rings on ebay are running around $9 each. I found a few posts with o-ring sites, so that's not a problem, it's more the size I'm not sure on.

The groove seems to be 2mm. When I lay a string along it and then measure its length it comes out to be 224mm - divided by pi that makes the inner dimension 71mm. So the correct o-ring would be 2mm cross section x 71 mm inner dimension?

But then I'm also thinking the old o-rings that I pulled out were rectangular in shape maybe partly from being compressed over time or maybe by design, so maybe a 1.7mm cross section would be smart if it'll expand in width a bit on installation? I'm also thinking my string trick isn't maybe super precise.

Can't find any other hints as to a suitable size and would rather make an informed purchase than just buying the ones off ebay 'cause they look right.' That doesn't always work out. Right now planning to buy a range of o-rings and just see what fits - still way less expensive than ebay. Any feedback would be appreciated. Thanks.

2.0 x 67
This is the size for the Keihin BS34 floatbowl O-ring for the KZ750H/E. According to Partzilla the early 400 shares the same part number O-ring so that suggests that's the size you need.

www.partzilla.com/parts/detail/kawasaki/KP-16019-024.html

Oh, and a few drops of superglue in the floatbowl groove works well to hold the o-ring in place during assembly.

2.0 x 67 OD or ID? I remember I posted something about this a few years ago. Can´t find my notes.

O-rings are typically sized by thickness and ID.