CDT. Several types of wormer, such as Ivermectin and Cydectin. Antibiotic, "just in case". Some type of treatment for coccidiosis. A drenching gun (I use a small one). Needles (I use 1" long needles) and the barrel to put the medication in (I use two sizes, a 6cc one and a 12cc one). A box of the type of rubber glove they use in emergency rooms.
I have not had enough coffee yet this morning... that's just off the top of my head and I know there are many more which some really smart people on here will tell you. There are lots of other things that make life easier too, such as one of those plastic calf pullers, which you will hopefully never need but when you do... and so on.
The main thing you are going to need to worry about is your horse products being dangerous for the sheep. As
@birdsforlife47 has said, sheep are copper sensitive. They should NOT BE ALLOWED anywhere near a product formulated for horses or goats. Don't get mineral salt blocks, for instance, get the plain white ones. And while it's safe for horses to eat grain formulated for sheep, it is NOT safe for sheep to eat horse grain.
On your sheep, it kind of depends what breed you have. I used to raise Jacob sheep and man, they were hardy and tough, and very "goat-like" in their behaviours. But I also had Rambouliette, and that was a completely different kettle of fish so to speak. I've had just about every type of goat there is in the US and right now have a dairy herd of Nubians. I de worm just as soon as they give birth, I worm in the fall and the spring, so three times a year, but it really depends on your local conditions. In some parts of the country, 3 would be too many and in some parts 3 would not be near enough. You can learn to do a fecal yourself, and then you will know for sure. Just Google "fecal exam kit" and you'll get lots of options.
