There is really no guarantee two chins will get along, each chin has it's own personality, so just because he got along with another chin before doesn't mean he will get along with a different one or that the new chin will get along with him. It's like asking if you will get along with some random other human because you had a friend before.
As to getting a male, yes, not because he will be more likely to get along with it but because if you put a male and female together you are going to get kits. Unless the chins are from genetically good lines and pedigreed and you have done research and have the money don't put a male and female together.
Also keep in mind that you should get another chin because you want another chin not because you want two to live together. You should be prepared for the possibility of needing two cages forever, bonding doesn't always work, or only works for a time then falls apart and they need to be separated. Also make sure you quarantine the chin for 30 days in another room before intros, and keep in mind bonding two together can take weeks to months, you can't rush it.