DUBLIN, Oct 1 (Reuters) - Growth in Irish factory activity slipped to a six-month low in September but remained close to all-time highs with the sector showing signs of inflationary pressures, a survey showed on Friday. The AIB IHS Markit manufacturing Purchasing Managers" Index (PMI) slipped to 60.3 in September from 62.8 in August and down from May"s record reading of 64.1. September"s reading was the sixth-highest registered since the survey began in 1998 and the survey showed a "very strong rebound" in the sector was continuing, AIB chief economist Oliver Mangan said. But it also showed signs that Ireland was subject to similar trends to the rest of Europe where shortages of raw materials, key inputs and labour were holding back manufacturing activity, Mangan said.While sub-indices measuring output, new orders and employment all fell, input and output prices both hit record highs. Difficulty hiring workers, order backlogs, supply chain delays and lengthening delivery times all contributed to inflationary pressures, Mangan said.