Collecting a really good blesbok is not going to be too difficult unless you go somewhere like Rhino Lodge in Mpumalanga and have to wait for them to stop running for a shot from 400m! That was quite tough! We have hunted blesbok in the Limpopo area twice and if we put our mind to it we can get a nice ram on foot in a couple of days, and probably nail another of the lesser species while we are out and about. We took a non-hunting friend on one trip and on a property near Rooibosbult, it took her an hour to get a very nice trophy which out-did all of my efforts. It was her second shot out of a rifle, the first was at a tin can the day before!
The caracal will most likely be hunted with dogs and trackers if that is the focus of your hunt. We were hunting plains game and my PH had organised for a couple of the workers on the property to get out into the bush with dogs and track one down. As soon as they were onto a cat we got a call and worked our way towards the action - it took a couple of hours of to get a shot at him as he didn't climb a tree like he was supposed to! It was a lot of fun and I really did want to bring home a caracal, but I don't have a great story to tell you and I have no desire to hunt them again.
Are these species add-ons to your safari or are they the reason for the trip? You could always go for a look around and see how you feel about the blesbok when you're amongst them, and if it doesn't get you excited go looking for caracal.
If you get out of the bakkie and hunt blesbok on foot, then I think you will work for your trophy and appreciate the animal and the experience that much more.