Chosen Solution

I am trying to replace the standoffs on the bottom casing of my 2017 Macbook Pro as they have become stripped and can no longer support a screw. Any idea of the correct size of the standoff that I should purchase? I cannot find the Apple specs anywhere. TIA for your help. Update (12/12/2019)

https://imgur.com/a/uhRfPqp

https://imgur.com/a/oBELIfQ Here is the bottom of the casing, Thanks!

The bottom cover standoffs are press-fitted into the case. They are not replaceable on their own. Apple does not offer them! The best you could do is find a machinist who can make a replacement and then press fit it in Heat the case and freeze the stand off so you can get a tight fit. The other option is replacing the uppercase.