If your just starting out Echo1 and JG make good ones. If your a seasoned airsofter you could go for a Classic Army, TM, or G&G they make excellent ones.
No your not going to get a good L96 for $100 heres a list of some snipers that ASGI has. Your not really going to get a good MP5 or G36c for $100 you might want to bump it up to $200.