I just checked the National Parks and Wildlife Service (NPWS), to see their statistics for recent years. 2020: > 44,000, 2022: 55,008, 2023: 78,175 culled. Everyone issued either a S29 or S42 permit to take deer in RoI are required to make a return on the numbers of animals taken and various other categories to the NPWS. Most stalkers I know in the RoI keep a record to assist the return. 350k per annum seems unlikely.