Getting another rabbit as a friend can be a good idea, but you do need to know what you are getting into. Even if they do get along, you still have to take the time to bond them which can be weeks or even months of 2 separate rabbits. There is always a chance that they will never get along no matter how hard you try.
Generally, the best paring is a spayed female and a neutered male. Same sex pairings can work, but it really depends on the personality of the rabbits involved. It can also work when 1 of the rabbits is intact, but that can be rare and really is based on the personalities of the rabbits.
Your best bet is to try a rescue and see if you can bring your rabbit for some bunny dates. She will be able to meet other rabbits and choose who she likes. If she gets along with one, then you could adopt that one. If she doesn't get along with some, then try others. You may need to go back again a couple weeks later if you don't find one so she can try again. You would need to do research on introducing rabbits so you know what to do in case the volunteers don't really know much about rabbits.
The breed, age and even sex don't matter as much as the personality of the rabbits. I have an almost 6 year old male who is bonded to a year and a half old female. He has been bonded to 2 other does of other ages (a bit older) and hasn't had issues. However, he seems to get along with just about any rabbit as long as they aren't trying to bite or attack him and he can get away if he needs to.
I would not count out any rabbit based on breed, age, size or sex until your rabbit has met them. You never know who they might get along with and want to give them the best chance.