Ok look up KingBrite on alibaba
They are a good place to start looking for parts and if you are new to electronics they are very helpful too.
You could use 3 or 4 50w cobs ether way I would get a LGSU250-1400D to power the setup this will do upto 5 cobs and is dimable it is over kill but I like to have room to expand.
CXB3590 (or your choice )
thermal tape or a tube of paste + Ideal 50-2303CR (LED mount)+ Ideal 50-2300AN (reflector mount) + Reflector KB-D82-90RF (cheapest one 90deg)
Pre drilled Heatsink: Φ133mmH70mm(for 50-65W per cob is a good start or you can go with a fan cooled up to you)
lol I made this easy