Sierra Leone 1924 New Colony Grid (Gold Coast Feet) - EPSG:2159

WKT

PROJCS["Sierra_Leone_1924_New_Colony_Grid", 
	GEOGCS["GCS_Sierra_Leone_1924", 
		DATUM["D_Sierra_Leone_1924", 
			SPHEROID["War_Office", 6378300.0, 296.0]], 
		PRIMEM["Greenwich", 0.0], 
		UNIT["Degree", 0.0174532925199433]], 
	PROJECTION["Transverse_Mercator"], 
	PARAMETER["False_Easting", 500000.0], 
	PARAMETER["False_Northing", 0.0], 
	PARAMETER["Central_Meridian", -12.0], 
	PARAMETER["Scale_Factor", 1.0], 
	PARAMETER["Latitude_Of_Origin", 6.666666666666667], 
	UNIT["Foot_Gold_Coast", 0.3047997101815088]]

WKT2

PROJCRS["Sierra_Leone_1924_New_Colony_Grid", 
	BASEGEOGCRS["GCS_Sierra_Leone_1924", 
		DATUM["D_Sierra_Leone_1924", 
			ELLIPSOID["War_Office", 6378300.0, 296.0]], 
		PRIMEM["Greenwich", 0.0], 
		CS[ellipsoidal, 2], 
		AXIS["Latitude (lat)", north, 
			ORDER[1]], 
		AXIS["Longitude (lon)", east, 
			ORDER[2]], 
		ANGLEUNIT["Degree", 0.0174532925199433]], 
	CONVERSION["Transverse_Mercator", 
		METHOD["Transverse_Mercator"], 
		PARAMETER["False_Easting", 500000.0, 
			LENGTHUNIT["Foot_Gold_Coast", 0.3047997101815088]], 
		PARAMETER["False_Northing", 0.0, 
			LENGTHUNIT["Foot_Gold_Coast", 0.3047997101815088]], 
		PARAMETER["Central_Meridian", -12.0], 
		PARAMETER["Scale_Factor", 1.0], 
		PARAMETER["Latitude_Of_Origin", 6.666666666666667]], 
	CS[Cartesian, 2], 
	AXIS["Easting (X)", east, 
		ORDER[1]], 
	AXIS["Northing (Y)", north, 
		ORDER[2]], 
	LENGTHUNIT["Foot_Gold_Coast", 0.3047997101815088], 
	ID["EPSG", "2159"]]

Data from @esri/proj-codes

{
  "wkid": 2159,
  "latestWkid": 2159,
  "gcsWkid": 4174,
  "macro": "PE_PCS_SIERRA_LEONE_1924_NEW_COLONY_GRID",
  "name": "Sierra_Leone_1924_New_Colony_Grid",
  "wkt": "PROJCS[\"Sierra_Leone_1924_New_Colony_Grid\",GEOGCS[\"GCS_Sierra_Leone_1924\",DATUM[\"D_Sierra_Leone_1924\",SPHEROID[\"War_Office\",6378300.0,296.0]],PRIMEM[\"Greenwich\",0.0],UNIT[\"Degree\",0.0174532925199433]],PROJECTION[\"Transverse_Mercator\"],PARAMETER[\"False_Easting\",500000.0],PARAMETER[\"False_Northing\",0.0],PARAMETER[\"Central_Meridian\",-12.0],PARAMETER[\"Scale_Factor\",1.0],PARAMETER[\"Latitude_Of_Origin\",6.666666666666667],UNIT[\"Foot_Gold_Coast\",0.3047997101815088]]",
  "wkt2": "PROJCRS[\"Sierra_Leone_1924_New_Colony_Grid\",BASEGEOGCRS[\"GCS_Sierra_Leone_1924\",DATUM[\"D_Sierra_Leone_1924\",ELLIPSOID[\"War_Office\",6378300.0,296.0]],PRIMEM[\"Greenwich\",0.0],CS[ellipsoidal,2],AXIS[\"Latitude (lat)\",north,ORDER[1]],AXIS[\"Longitude (lon)\",east,ORDER[2]],ANGLEUNIT[\"Degree\",0.0174532925199433]],CONVERSION[\"Transverse_Mercator\",METHOD[\"Transverse_Mercator\"],PARAMETER[\"False_Easting\",500000.0,LENGTHUNIT[\"Foot_Gold_Coast\",0.3047997101815088]],PARAMETER[\"False_Northing\",0.0,LENGTHUNIT[\"Foot_Gold_Coast\",0.3047997101815088]],PARAMETER[\"Central_Meridian\",-12.0],PARAMETER[\"Scale_Factor\",1.0],PARAMETER[\"Latitude_Of_Origin\",6.666666666666667]],CS[Cartesian,2],AXIS[\"Easting (X)\",east,ORDER[1]],AXIS[\"Northing (Y)\",north,ORDER[2]],LENGTHUNIT[\"Foot_Gold_Coast\",0.3047997101815088],ID[\"EPSG\",\"2159\"]]",
  "description": "Sierra Leone 1924 New Colony Grid (Gold Coast Feet)",
  "authority": "EPSG",
  "version": "5.2(8.1.2)",
  "deprecated": "no",
  "areaname": "Sierra Leone - Freetown Peninsula",
  "extent": {
    "slat": 8.32,
    "nlat": 8.55,
    "llon": -13.34,
    "rlon": -13.13
  }
}