Seat back o-rings again

I am redoing the seats on my series 2 and bought an 40 o-ring kit from the usuals. I figured after 40 years it was time to replace the o-rings. The new ones are much smaller in cross section and actually longer than the old ones. WTF! So, I put on my engineer cap and start researching on the internet. I estimate the original ones when new (and not stretched out) were 5/16" in cross section and 2" ID. EPDM rubber is a good weather resistant choice. A metric 8mm cross section o-ring will also work.
I have requested a quote from 1 vendor for 8x54mm EPDM o-rings. I will let you know what I find out. Does anyone have a source for the correct rings?

Here are some from one of the usual providers of Jag Etype spare parts.

Here is one from the UK
Here is another from the USA

Thanks for the links. I am in the USA. The XKS has no dimensions, I can’t call them because of covid-19… the bassetts at least have a ruler in the photo so I can scale and measure. They also seem larger that the old ones. I may just keep the old ones, but will keep searching.

That proves that little to no effort goes into research for the correct parts. O-rings come in nearly every size and the correct ones are available from kit suppliers in the know. Not even the effort to buy a bag to measure them.