eBay has the AMD Ryzen 5 1400 4-Core Desktop CPU (YD1400BBAEBOX) brand-new condition for $135 with free shipping. Retail price: $170. Frequency: 3.4 GHz precision boost, 4 Cores/8 threads Unlocked, Cache: 2 MB / 8 MB (L2/L3). Has good Amazon Reviews.
eBay has the AMD RYZEN Threadripper 1950X 3.4GHz 16-Core Desktop CPU for $780 with free shipping. List price: $1000. Features 16 cores / 32 threads, 3.4 GHz base and 4.0 GHz precision boost clocks, socket sTR4, DDR4 support.