Just some ideas
1) just order pullets
2) get an autosexing breed
3) get BR's or Dominquers--can sex with accuracy after practice
4) get a red roo and silver factor hens and hatch your own sexlinks
5) buy straight run and be surprised!!
Are you buying them from a hatchery? If so, you can order them as males or females. They can be sexed at birth by hacheries with about 90-95% accuracy.