Send your fired brass to C&H Tool and Die and they will make you a die that fits your chamber.
Since this cartridge headspaces on the rim, often times the chambers are cut generously in the shoulder dimension. The shoulders tend to blow forward quite a bit. If you FL resize your cases, and set the shoulders back to original dimension, you may have some real problems.
The die is less than $60, and your brass fits your rifle perfectly.
My $.02