I would imagine dealers are 0.1-1% of the population (say .3%) and the FBI says roughly 13% of homicides are gang related which is probably a rough proxy for the number of drug dealer related homicides.
This would put dealers as having a homicide rate approximately 40x the base rate. This seems right to me.
To be fair, have to measure folks in the same socioeconomic class and geography but not in gangs and compare?