I can advise you that the Immigration Service Delivery (ISD) of my Department does not issue individual immigration permission letters to persons who have a permission to be in the State.
However, any person who has an immigration permission must have an in date Irish Residence Permit (IRP) card, which can be presented and accepted as proof of entitlement to be in the State and the conditions attaching to that stay.
The IRP card will display the type of permission the person has, represented by a Stamp number and the expiry date.
Information on the different immigration permissions and the conditions that apply to them is available on the Immigration Service website at: www.irishimmigration.ie/registering-your-immigration-permission/information-on-registering/immigration-permission-Stamps/#passport-Stamping