Dear sir, is it possible to change the INNER.

Normally, yes, but often you won't find replacements at the dealership. You may have to find them at an auto parts store. GM is always experimenting with new designs on cars they sell to the public, so it's often impossible to find replacement parts made by the big name brand parts manufacturers. The only listing I could find for your model is for the European model. There's no listing for an inner tie rod end for the Canadian model.