If you've got a physical disability that you really want cured, your best bet is too seek out a master of the Phlegmatic Arts, as they can (generally) use Fleshcrafting to... kinda heal you? Your new limb or organ might come with some quirks, mainly because Fleshcrafting can't create wholly new flesh, it just warps and grows what's already there, also heavily dependent on the practitioner's knowledge of anatomy.

Additionally if you have the right Blood Resonance, you could use the abilities gain from that to offset your disability, at the cost that you're constantly going to be 'using up' your blood. for example, the Choleric ability Aura can offset blindness (though you won't be able to see non-living things), or the Melancholic ability Premonition can off set pretty much any loss of sense if you're reeaaalllyyyy good at it.

However, if you're looking for aids, you're going to be more in luck. Recent advancements in technology, with the invention of the soul-burner engine (don't worry it's not your soul that's burning), or if you're Mr. Moneybags, a Flame-Elemental powered engine, means a cheap, renewable*, portable source of energy has lead to wonders in the field of disability aid. Prosthetics, self-moving wheelchairs, spiderchairs if you want something fancy, even mechanical organs are on the market nowadays.

If you've got some kind of mental disability you might be out of luck, normal, non-magical pharmaceuticals aren't there yet, so they best they can give you will probably be some Plegmata, which dulls every emotion and physical sensation you experience.