Well, you can take a wild guess why no one is elbowing their way to post here and you known better
but i'll take my chances and throw my 50 cents in. I just like to keep it a tad real, I mean historical:
1. I really like the old coat of arms of Persia, you know than lion holding a shamshir and the rising sun. Goes back to the beginning of Qajars in late 1700;s or earliear. Here is a reminder but look further for a better copy, they are out there:
http://www.crwflags.com/fotw/images/i/ir~39wp.gif
2. Take a look at the current flag of Saudi Arabia, blends both of your requisites, Islamic arms and religious caligraphy: a
saif and the
shahada. In case you need a visual reminder:
http://www.crwflags.com/fotw/images/s/sa.gif
3. There are so many swords or pieces of armour with inscriptions out there, just see what catches your fancy. There is so much out there from Ottoman, Persian or Mughal, its sick. Here is a Khula-Khoud helmet design...
ex:
https://www.metmuseum.org/toah/images/hb/hb_50.87.jpg
P.S. Dont parade something like that on your car
Also keep I say to keep it historical as real, youre English speaking Caucasian dude living in North America unless youre the next Eminem