pods8 laid out a ton of useful info.....regardless of what you get or use, ensure you are well versed in rappelling, anchor building, knots and understanding the safest techniques for lowering/hauling/rappelling, etc. Rappelling is one of the more risky parts of climbing, as it is so dependent on technique, integrity of the anchor, knots and gear.
Here are my two cents (I have climbed for about 20 years, rock/ice/alpine here in MT as well as Canada, the Tetons, etc. so am pretty familiar with what you may need. And who knows, you might just get the climbing bug too!)
A good all around "kit" to get you and/or your pack/goat/partner off something like a cliff, I would recommend the following:
Rap Line II -- this is not to be used for lead climbing, and I would say if you need to lead something on a goat hunt, use pro, etc., then it might be too steep to be safe. This line is small diameter (6mm) and works really well as a rap/lowering line. Word of caution -- thinner lines are lighter and pack away well, but good gloves when lowering or rapping off of something are necessary, as is the right belay/rappel device. The reason for such a thin line is I want to take this with me on the hunt, not have it back in the truck, so weight is important. Having 60-70m of 9 or 10mm static line in the rig would also be a good option.
For a belay device, t
his one works, but I would pair it up with TWO carabiners off the belay loop to increase friction. Also consider learning how to apply a Prusik to the rope as a backup.
Harnesses -- lots of options, but
if you want superlight, here you go. Doesn't get much smaller or lighter. Will work to rappel off of something no problem. Yes, you read that right - under 3 ounces for the whole harness, size Large.
Anchors -- Get a few 12mm Dyneema slings in 30 and 48 inch lengths, as well as 2-3 locking carabiners. These can be used for LOWERING something or someone off of a stout tree, etc. by slinging the tree and running the rope through the carabiner. I won't go into active or passive rock protection...that is a whole other topic.
Here is a great article on the basics:
https://rockandice.com/how-to-climb/how-to-rappel/
There is a place I ice climb frequently that is also goat country, and I have used large, strong trees as my rappel anchors. One climb in particular requires three rappels (each about 80-100 feet long) so we use TWO climbing ropes (each 60m in length) tied together. When done safely, it is a fast way to get off something, whereas down-climbing it would be foolish or just plain deadly. Also, by using the trees we don't leave behind any anchors as we pull the ropes after each rappel. A pretty common tactic in alpine climbing areas.
Let us know what you go with, or if you have any other questions! Good luck and be safe.