There are several (actually quite a few) SME parts suppliers.Any suggestions on where to purchase a heavier counterweight? I'm clocking 13.18g right now.
You can get them from eBay. Japanese sellers tend to be good to deal with.
There's a Canadian company that deals in SME 3009 parts.
https://www.smetonearms.com/index.php?main_page=index&cPath=3_8&zenid=lgu199rbu50ft7q0g80d2a8kj1
There are several SME parts places in the Europe, too.
https://www.riversideaudio.ch/english/sme-spare-parts/