The definition you gave doesn't match EPSG:7239 which is a coordinate operation for a county in Indiana, USA. I edited the code/well-known ID out of the title question because it's misleading.
The projection parameters match a Romanian projected coordinate reference system. The current definition in EPSG is EPSG::3844, Pulkovo 1942(58) / Stereo70. In EPSG, the map projection algorithm is called Stereographic, but in Esri software it's called "Double Stereographic" because we already had a Stereographic projection prior to adopting the EPSG dataset. Esri also has an older version of the same projected coordinate reference system called "Stereo_70" and based on the geographic coordinate system, Dealul Piscului 1970. Basically, it's an alternative name for Pulkovo 1942(58). The WKID for this one is 31700.
Redefine the data to one of these using the Define Projection Tool.
Once you've done that, you can use the Project Tool to create a new dataset using WGS 1984 (EPSG:4326). If you use 31700, use "Dealul Piscului 1970 to WGS 1983 3X" as the geographic/datum transformation. If you use 3844, use Pulkovo 1942(58) to WGS 1984 (19) as the transformation.
The data with its current definition is unusable in Esri software because the coordinate reference system definition is not correct and won't give the correct coordinate values. If you try to overlay this data with other layers, it should not line up.
Disclosure: I am an Esri employee who focuses on coordinate reference systems and transformations. I'm also a member of the subcommittee that maintains the EPSG geodetic registry.