Interesting J. Stevens Arms & Tool Co. double!! Generally speaking, the No. 350, 360 and 370 weren't engraved.
After the J. Stevens Arms & Tool Co. changed their method of barrel manufacture from the mono-bloc style of the No. 350, 360, 370 and briefly 380, they changed to a chopper-lump style barrels which they called demi-bloc. The guns then became the No. 355, 365, 375 and 385. In that series the No. 375 and 385 were engraved --