I am not sure what you mean by "engraved grips." The original grips were black hard rubber (plastic like) with checkering and the Husqvarna trade mark. The gun is the FN Model 1903; the 1907 was the Swedish designation. Husqvarna began making them in 1917 because they were no longer avaiable from FN due to the German occupation of Belgium.
The original caliber was 9mm Browning Long, a more powerful round than the .380 ACP, but now unobtainable in shooting quantities. The importers had chamber inserts put in and the recoil springs cut down to allow them to work with the .380 ACP.
Value-wise, and assuming the grips are original, you did all right; those guns have been selling as high as $600+, with unconverted ones and FN-made guns going for around $200 more.
Jim