Do not introduce a rabbit to Lori unless he has been neutered, and a few weeks to a month has elapsed since his neuter. An unneutered male would likely be humping her constantly and that will cause fights, which can lead to severe injuries. The age of the new rabbit isn’t all that important, but him being neutered is.
Most rescues and some shelters/humane societies will neuter their rabbits, although a lot of times the shelters will wait until someone actually adopts a rabbit before they spay or neuter them. So, if the new companion that you get has just been neutered, you will have to keep him in a separate pen for around a month before you can start bonding. Some rabbits will go into a post neuter craze, and it’s really best to not try to bond with all those fluctuating hormones.
I saw that you had another thread and said that your vet said it would be okay to go ahead and start bonding your rabbit next week, who was just spayed 2 days ago. I think it would be best to let her hormones settle down first, and to make sure that she was completely healed from her surgery before bonding is attempted. You could go ahead and bring home a new companion and keep him in the same room, just not right next to her pen, but wait a little while for the bonding. He would need to settle in for short while anyway.
I find that a good way to bond is by using an x-pen. I have bonded 5 pairs of rabbits over the years. My husband and I get in the x-pen with them, to break up any fighting (some scuffling is normal) or to stop any excessive humping (some humping is normal) or to comfort a rabbit who seems a little overwhelmed. Start with a few minutes and increase the time they spend together each day.
Here are 2 good articles on bonding:
https://binkybunny.com/BUNNYINFO/tabid/53/CategoryID/9/PID/940/Default.aspx
http://rabbit.org/faq-bonding-multiple-rabbits/