There is a decided lack of magic loot in my campaign, it has been that way since day one. Sorcery is an unreliable beast and binding it in an object is a poor decision, the longer it stays put, the longer it has time to degrade and grow more and more unstable. Eventually, the item just explodes in a blast of sorcerous fun. Unlike with spells, these disasters are pretty straightforward, the object is destroyed and the spell causes a sorcerous explosion. There is fire, noise, and a blast crater dependent upon the power of the spell. If the object is made out of steel, well, we've got shrapnel. Anyway, you get the idea.
Now, magic items do exist in this world, and the guys are literally in the Mecca of sorcery in my world, if they wander out into their district, they can come home with a bag full of useful stuff. They don't ever wander outside of their mansion though, so they have nothing. I'm not sure why, but kudos to them for their minimalist lifestyle. Technology is after all, safer...unless John's rifle explodes.
Does this unreliability mean that there isn't much diversity in magic items in my world? No. There are always nutjobs trying to build crazy deadly shit, and this extends to fantasy worlds penned upon the fabric of my grey matter. The unreliability also means that if you leave a magic sword in a cave, it will probably explode before players have a chance to loot it off the corpse they find it with. Back to the deadly shit, there are magic guns of wolf-iron that are fueled by sorcerous energy (you sacrifice a spell slot and that determines how many shots you have with the weapon). Others fire literal mind bullets (make a Psicraft check and fire the weapon as many times as you want as long as you maintain your psionic focus). There are potions that are basically an adrenaline shot for the sorcerous nature of Fell Humans and allow them to use their own sorcerous potential to power charged magical items. There are healing potions and bows that shoot lightning, and even bladed weapons that have bloodletting bits that are shaped edges of sorcerous force.
I suppose you can follow this thought to the next tier of loots, artifacts. We've established that there is a wide variety of magic in my campaign. Are there artifacts as well? I would say yes. Are they spoken of like The Sword of Kas and the Axe of Dwarvish Lords or the Hand of Vecna? No. You can't make a Streetwise check or Knowledge (Arcana) check and come up with a dozen rumored magical artifacts in my campaign world. If your characters spend six weeks in a library with tomes on sorcery available to them and expend a pile of marks following up on leads, you could probably come up with a name or three or an idea of what an artifact might be capable of. You could then go on a quest to a better library in some far off country like Vyanthnem or The Fallen Empire of Man, and try and track down further information.
Unlike 4th Edition, you can't wander into a cave as a first level character, and then wander back out with a few thousand gold pieces worth of magic items. Every back woods town does not have a resident sage dude that will speak of ancient rituals and artifacts and that cave over there that used to be part of an ancient temple that no one else has ever investigated in the past thousand years so all the magic loot is still waiting to be picked up by adventurers. Long sentence, I know. You'll be fine.
I guess I'm saying that if The Robust Five (More Or Less) decide that they need to amp up their situation with magic weapons, and decide to take the initiative in the matter, they could get their hands on a magic arsenal and are in the prime location to do so. Although, I suppose with only four scenarios left in the campaign, it is a little late to be running off on wild goose chases for unreliable artifacts.
Another question comes to mind. Do artifacts act up and explode? Hmm. I'll just hand wave it and say they're made out of star metal or some shit.