Power/Welder Family postcard sent from Ireland to Texas

I have a postcard sent from Ireland with a photo of the Dunbrodey Abbey in County Wexford, Ireland.  I am still unsure of the exact date.  The postcard is made out to Mr. Jim Power and sent to Vidauri, Refugio Co, Texas.  The back of the card reads as follows-

"We came here just to see the town where grand-father Power was from.  It is a quaint old place and full of history-We spent the day in Waterford the home of the Powers-K. Welder

I am a direct descendent of Col. James Power, the Irish-born Texas Empresario.  Col. James was my 4th great grandfather.  I acquired this postcard from my grandfather.  I am interested in the year of this postcard, as well as the possible worth of the postcard and the stamp.  Any information would be greatly appreciated.  I am not opposed to selling the postcard for a fair price to an interested individual or company.