You used to be able to purchase everything but not "choose" your tag type. You could then choose your tag type at a later date. You cant do that now, so I just left Elk off the purchase until I decide.
You can still choose later. I bought the Deer, Elk,Bear, Cougar with discounted SG combo and didn't have to declare my weapon choice for deer and elk yet. I got my bear, cougar and turkey tags in the mail last week without the deer and elk tags.