RZ Jets seems to show they were never leased out to anybody else... I also checked just one 737 which showed lease details.
Odd, opened my elderly copy of Airliner Production List - a whole sequence of BAC 1-11s (c/n 43 - 62 which included the Irish quartet), are missing from the list, looks like a printer's error when typesetting or however they did the printing 30 years ago. Never noticed before!