I just checked the "When Radio Was" website and discovered that this Monday (December 23rd), they will be rebroadcasting Jack's 1940 "Christmas Shopping" episode.
"When Radio Was" is nationally syndicated; but for most people in the Eastern and Central portions of the United States and Canada, the best bet will be to tune-in Chicago's 50,000-watt WBBM, 780 on the AM dial, at 1:05 A.M. Eastern Standard Time (12:05 A.M. Central time) on Tuesday, December 24th (late the night oft he 23rd if you want to put it another way). Jack's 1940 Christmas show will lead-off that installment of "When Radio Was".
Additionally, the show's website (http://www.whenradiowas.com) has episodes archived for one week after they air, so you will be able to hear this episode through December 30th.
(Usual disclaimer: I don't work for "When Radio Was", any station carrying the show, nor know anyone who does. I just wanted to spread the news)
Merry Christmas, Happy Holidays, and a Happy New Year!