The Hornady American Whitetail 139 grain factory load has a good reputation at the range I frequent and it is the least expensive 7mm-08 factory ammo in this area at about $22 per box.
If your Wife isn't recoil sensitive, I'd suggest that she give them a try, since one of the keys to her success will likely be practice shooting the T/C at longer distances. The more practice she gets in, the more comfortable/confident she is likely to be when the shoots present themselves in the field this coming October.
Antelope and mule deer aren't any harder to kill than whitetails. Shoot any of 'em through the lungs and they all die pretty quickly.
