I posted links to the 10W and smaller variety of stuff I am toying with now. Buying in bulk quantities from China nets you a deep discount. The catch is the items take a month to ship. If I were marketing lights, I would not mind the slow turnaround times in sourcing parts. But I'm making these things for my own personal use. Paying 10 bucks instead of 3 is not a financial stretch, and I get the stuff in 3-5 days. YMMV
These ones are $1.75 each shipped in single or small quantities from China:
10W watts High Power SMD LED Chip Light Beads White Red Blue Yellow Grow Lamp | eBay