There's a wealth of stuff in the papers. However, nothing to assist your search for Mary/Tom in Cardigan post war apart from snippet already posted with his Aberystwyth Road address.
Tom Elfed's father was very well respected - council work, conductor of a choir, adjudicator at Eisteddfods etc
Merthyr Express, 22 Apr 1939
Only snipped part - check FindMyPast for rest which mentions his link to GWR.