https://www.ebay.co.uk/itm/8th-Irish...QAAOSwIlBehz21
Not only is this not a WW1 badge but I believe all the die struck examples one comes across are duds. The badge is an officers caubeen badge introduced when the unit was reformed in 1939. The design is based on a pre 1922 officers headdress badge and original examples are die cast silver plate with a named slider. Two examples are illustrated.
A group photo of officers of the battalion during WW2 is attached,
P.B.