You have 20 of those heatsinks?
If you’re not buying heatsinks you can do something like @Bogleg with those $9 citi 1212’s. You can run 5 on an hlg-185h-c1050a at 40 watts each. Would be extra protection on the cooling. 3 drivers worth of that would probably be fine.
For about $20 per cob you can jump up to a luminous com-22. Would be more efficient like the bigger citi, the vero 29, or the cree cxb3590.
Any of those will be fine. If you’re not buying heatsink and we’re looking at 50 watts per cob, you’re gonna come in way under your budget either way.
But I think doing something around 3-4 200 watt bars would be your ticket. You can have separate dimming on each, and the flexibility to move them around as needed.