Commercial Electric GU10-16 120-Volt 50-Watt Halogen Bulb (3 Pack) EE750FC-H - The Home Depot
Simply Conserve ENERGY STAR GU10 50-watt EQ 50-Watt EQ LED Mr16 Soft White Gu10 Pin Base Dimmable Spotlight Light Bulb (100-Pack) in the Spot & Flood LED Light Bulbs department at Lowes.com
GE Warm White 50W Replacement LED Dimmable Track Recessed GU10 Base MR16 Light Bulb
GU10 LED Light Bulbs, Dimmable 5000K Daylight White 5.5W (50 Watt Equivalent), Full Glass Cover Reflector, 25000 Hours, UL Listed, Energy Star, by Mastery Mart (Pack of 10) - - Amazon.com
GU10 LED spot 5 Watt Dimmable 6000K daylight white (replaces 50W)