Yes, that looks original. There were two types of quartz movement in these watches a cal 1441 and cal 1438. This configuration (caseback, crown and mercedes hands) you show was the earliest (1988-89) and should have the cal 1441, a very accurate movement that Omega only used for a year or so.
The trouble is that many of those movements were swapped out in services either for the 1438 or an ETA equivalent. The only way to know is to look.
The price seems extremely reasonable so worth checking everything is functional.