Could someone tell me the part number for the 8Pin to 2 x 8(6+2) Pin PCI-E VGA Cables that comes with EVGA 1000 G+ PSU? 120-GP-1000-X1  
 
Thank you!

I think that's 8 pin to 8 and 6 pin, instead of 8 pin to dual 8 pin.

Cool GTX is correct, the cable is a dual 8pin (6+2), from an 8pin that goes into the PSU.  Our individual cables (not the cable sets), could be taken from any of the power supplies that they are compatible with (except for GM, of course [surprise! you won the super-short cable!]).
 
I could give you the internal part number that's used as part of the 1000G+ set, but it would honestly get you nowhere since you won't find it online.