Another question, will this fence be left put up at the cabin or will you be taking it back down and storing it when you leave?
If you are looking for a sure enough sturdy fence that can withstand pretty much anything a horse can throw at it, you will probably be better off just buying some panels from TSC or your local Co-Op. I got mine from a company in Abilene, but they don't mass market their panels to stores nationwide. They are both cheaper and much tougher than those orange or green tubing panels you can get.
If you are going to be putting it up while you're there and then taking it down when you leave, I suggest some of those step-in t-posts with at least 3 strands of wide electric tape hooked up to a charger (either solar or plug in).