Saw these led chips popping up on ebay lately, look like clones of the Radeon board. seems to me it would be a pretty decent basis for a diy light. basically uses the same led layout and cree diodes that radeons use. match it up with some LDD-H drivers a 6in Makers LED slim heatsink and controller of your choice and you have a pretty affordable powerfullight.
https://www.ebay.com/itm/5-Channel-...897177?hash=item1caddb0859:g:SkEAAOSw945bF566
https://www.ebay.com/itm/5-Channel-...897177?hash=item1caddb0859:g:SkEAAOSw945bF566