I would say that, visually, the pipe character is an excellent choice. I don’t think it is a good idea to revise your whole Mac workflow just to accommodate posting a few images here.
The easiest solution would be to copy any RAW file, that you want to show here, to a dedicated folder and rename it from within PL. This will ensure that the original filename, the DOP filename and the reference to the RAW file in the DOP all get written correctly.
So…
- Edit original image in PL
- Copy RAW file and DOP to dedicated “posting” folder using Finder
- Open copied file in PL
- Rename file in PL
Then you can post the file and the DOP from the “posting” folder to here and it shouldn’t upset those poor souls who still use Windows 
