Just did my 112 and I used the Burris xtr bases and rings. The base is a 2 piece and I did have to file some off for the scope to fit right (eye relief)the adjustment ring was touching.
As for rings if you use the Burris xtr you will probably need the LOW ring because they are made a lot different height wise than standard rings, but there is a size chart on their web site or in the catalog from Burris.
I have these on 4-5 rifles and find them to be extremely durable and well made.