I like Roma pads; they're well made and should last just about forever if you take care of them.
I notice you bought fenbendazole. This is the time of year to get rid of tapeworms, so I would have gotten Zimectrin Gold instead of the SafeGuard. You can always put that dewormer away for now, but if you want to use it, there's certainly no harm.
The fleece girth is nice, but I notice it has elastic only on one end. I prefer elastic on both ends, so I can tighten the girth evenly on both sides. Certainly nothing wrong with it, I'm just voicing my preference.
I take it you already have the blanket, and just need leg straps?
Yes, buying horse related things is very expensive. Which is why I take good care of my tack. Can't afford to replace it!