Mac Pro 12-Core: Two 2.66GHz Intel Xeon 16GB 1TB Super Drive Intel Xeon 2010 - Refurbished
Mac Pro 4,1 5,1 x5690 CPU Upgrade Kit ND - Zephyr's Market
X5680 Matched Pair Apple Mac Pro 5.1 3.33GHz 12 Core CPU Intel Xeon 2010 2012 US | eBay
I found a pile of old xeon, two of them being pga instead of lga, pretty fun ! They all date from before 2010, the strongest ones being 4c8t : r/ intel
OWC 12-Core 3.33GHz Intel Xeon X5680 Westmere Dual... at MacSales.com