Yes, I wouldn't mess around with using something that doesn't belong in there, order the correct shims.
That's "shim" by the way, not shime. Ryhmes with "Tim". Plural is shims.
You could take it apart and try removing the shims that are there to see if it increases or decreases the gap. Logical thinking is that it would close up the gap bt removing, but I'm not too sure if this is the case. I'd try it to see, maybe you won't need to order the shims.