It happened in F1 in 1963 at the Mexican GP. That was the first and only time a #13 had been in a race until Pastor Maldonado chose 13 as his personal number in F1 some years ago.
NASCAR skip the 13th pit box, so when you choose what pit box to use you jump from 12th to 14th. Which incidentally means that box 14 is one of the most popular and best ones.
IIRC it also happened a long time ago that grid position 13 was called 12a...
All in all, as we know, skipping the number 13 and calling it 14 doesn't change that it is the 13th one.
It also seems to work fine for Rebellion.
Let's hope I didn't jinx you
I did actually consider putting another number on your car...