As you probably know, there's more to it than the call, but I have successfully called lions with an old Weems Wild Call jackrabbit voice (which is an antique collector item no longer available) and a Modern Calls jackrabbit voice, (#101 jackrabbit I think is what Modern Calls labels it). Also had one come to rattling when I was after whitetail.
The Modern Calls makers are super helpful on the phone. I like the raspy deeper Modern Calls jackrabbit sound, and you can immitate a rabbit or a fawn with that same call easily, and do a pretty good lamb also. Then there is a world of electronic options with lots of people ready to take your money. Good luck! It's fun.
If you haven't called much, learn to do it with hand calls, and then you'll know what works and some of why, and what you want if you decide to buy more expensive toys.
