Spunjer , I'm not saying my assumption is anything other than that ; I could well be wrong .
When you look at arabic dates on Indo Persian stuff often the first number is marked this way ; so putting two and two together led me to believe that this could be true for swords made in a Muslim nation but dated in different numerals .
YMMV ...
The town where your sword was made is now known for the pellet guns they manufacture ; interesting , no ?