Theres probably thousands of sites with the same old samples used by everyone who's tracks sound the same.
I'm sure there are loop sites etc with what you need. But my advise is be original. A debatable paradox when sampling but its what you do with it the sets you apart.
"Calibre, the man with an ear for a sample" SP:MC
Many pros would love to be able to source samples like that man.
Listen other genres of music you like, if you like a section, sample it. Theres no rules with sampling, only copyright laws.