Hello jkamst & Justin,
Seems like Prolyte still has a download link for the DWG symbols on their website: https://www.prolyte.com/en/support/symbols/dwg-symbols/circles/30-series
I also uploaded the Prolyte DWG circle files I still had in my Archive, in case the link does not work anymore.
Good luck with the symbols and hope to see them soon in the resource manager / Prolyte libraries
Circle truss.zip