Losi 8T wheels are 3.8 with 1/2" offset. Proline has released some dish wheeels which are 4.0 diameter, you can stretch 3.8 tires on them. They even glue the same as Traxxas tires.
I have a couple sets of race tires in 1/2" offset, dish wheels with bow-tie type tread pattern and some crimefighters as well. Great for bashing, very durable too. I'll let them go cheap. I have a 40 gallon container overflowing with tires perfect for a Revo, Savage or any 1/8th truck for that matter. The same type of tires/wheels I used to run on my Revo. 17mm hexes btw.