As seen at Calguns, an AR-15 with a laser engraving of Konoha leaf:
At the thread, some of expected confusion and typical Naruto bashing is present, but not as much as I feared. Also, some of the posters appear to know what /k/ is. Perhaps I should be disturbed.
My own BLR 81 has an aluminum receiver with wide flat surfaces, so it would take engraving nicely. But I guess I'm not fan enough to take a leap.