The 110 has a 12" speaker, no amp, and a different looking cabinet than other classic Leslies. Since there is no amp don't expect a boost in volume, so it really depends if you need to compete with anyone whether this is sufficient. No upper horn.
It is made for spinets and should be a good match for your M2. The hook-up is relatively simple, but I will let someone else explain that.
Worth $100? May be a bit high it will work, won't cost you a lot (are you willing to spend more if you don't really need it?), and the cabinet doesn't take up a lot of space. Maybe you can get the price down, but the convenience of being able to get it right now might be worth it to you.