You are correct, the presence of sysmergearticles on the live system indicates that it is involved in Merge Replication, or has orphaned metadata from a previous Merge publication or subscription.
On the live system, in Object Explorer in SSMS, expand the Replication node and publication/subscription nodes. You will want to determine if the live system is involved in an active Merge topology or if the Merge system tables are orphans from a previous topology. You can run the following query to determine this:
select *
from sys.databases
where is_published = 1 or is_merge_published = 1 or is_subscribed = 1
If the live system is involved in an active topology then you will want to determine if it is a publisher or subscriber. From there you can script out the publication and subscription(s) by right-clicking the publication or subscription in Object Explorer -> Generate Scripts... Details on scripting replication can be found here in Scripting Replication. Then you can recreate the topology on your test system.