Yes, they are ONLY the pads (no irons attached :) ). But I have my cheap fillies irons for while, so I just need pads. They come in different sizes. Just pick the one you need (in your case 4 3/4, BTW that's what I have too).
What type of boot do you use? With a rubber soled boot, my foot won't slip off of bare metal. With leather soles, it can slip off of almost anything, although rubber pads help. I switched to these recently. I find them comfortable, and it is easy for my foot to stay there...and to get out, when I want that. I use them without the leather pads, which I hate:
The standard fillis stirrups without pads are pretty slick. I tried that for a while, but didn't like it. The Australian 4-bar stirrups have a rough surface, and are twice as wide as a standard stirrup. Being metal, they behave like standard English stirrups at the end of the stirrup strap. I have a tendency to point my toes down when nervous, and the extra width makes that hard for me to do. I tried them with the leather covering, but my foot would slip too easily. I don't jump or show or do anything special, so I don't know how well my riding reflects yours.