Well, there's the VR Cover brand ones sold through the Oculus site. Keep in mind that those are incompatible with the glasses spacer. Annoyingly, the Kiwi facial interface and pleather pads are Quest 1 only, they aren't compatible with the Quest 2. AMVR makes ones that appear to be a cover that slips over the standard interface. there's also this one, but I don't know how well it works or how comfortable it is.
If you have a Quest 1 though, I can't recommend the Kiwi ones enough.
I would definitely suggest getting an after market facial interface or cover though. The foam one Oculus uses as the stock interface is not hygienic. It's fine if you only use it for things like VR chat and watching movies. If you're doing anything that's physically active (such as Beat Saber) though, it'll quickly get nasty due to soaking up the sweat.
These silicone covers are great from VR cover. Buy a couple and you always have a nice fresh replacement available for after a sweaty BeatSabre session.
I have the VR Cover brand ones, and ya know what? I find I actually can't use them. Aside from the glasses spacer not working with it, my Quest 2 keeps refusing to stay turned on when it's attached. I turn it on, and sometimes it works fine. Other times it immediately enters sleep mode for reasons unknown. That doesn't happen with the original interface.
I can only assume that VR Cover's interface is interfering with something. How? No freaking clue. But it's kind of evident something is happening. I'm currently looking for a better option. Too bad the Kiwi brand one with a vented interface isn't compatible with the Quest 2. That one is comfortable, and does a great job of preventing fogging up or sweat forming inside the viewing area.