How long would this date/apricot/walnut loaf keep if I want to send it in the mail?

I am not familiar with that recipe and the only quick breads I make get gobbled quickly, but I have a shipping hint. USPSP Priority Shipping is awesome. 3 box sizes and one price no matter the weight. I mailed a 7lb box of goodies from Portland, Oregon to North Dakota for $12.65. It arrived in 2 days.