The way I see it, the ONLY options you have are either to:
1) Get one rabbit (especially considering the size cage you have and if they won't get LOTS of free time to run around)
2) Get two from the shelter. They can help you bond them, or find two that will show "love at first sight" (easier bonding process).
However, if you must must must get them from somewhere else, get two males. The girls will get cancer. Are you prepared to pay for those kinds of veterinary bills? To risk her death within 5 short years? To subject a bunny to cancer is cruel IMHO.
Males, if introduced properly, or raised together, can get along. However, when their hormones start to kick in, they probably WILL fight, and I promise you, it will be terrible, unpreventable without neuter, and impossible to fix without the neutering of both. And, bunnies hold grudges, so you might have a hard time re-bonding them if you let them fight tremendously, get them fixed, and then try to re-bond them.
Shelter shelter shelter!!!
Good luck, and congrats tho on getting a wonderful pet