https://www.matterhackers.com/store/c/3d-printer-hotend-heater-blocks?ref=mh-subnav-TR28R
3D Printer Hotend Heater Blocks | MatterHackers
Replace or upgrade the heater block on your 3D printer's hotend with the parts in this collection.
heater blocksprinterhotendmatterhackers
https://www.hawkperformancediesel.com/c-899-products-engine-performance-engine-heater-blocks.html
Products - Engine & Performance - Engine - Heater Blocks
engine performanceproductsheaterblocks