It looks like MG or mycoplasma gallisepticum, or coryza. Coryza typically smells bad. Is she gurgling or rattling when she breathes? Have you recently added any new birds that could have brought this into your flock? These are chronic carrier diseases, and once the whole flock is exposed...
We need to se her wearing her cone! For respiratory disease (if you think that is what it may be) besides Tylan there is Gallimycin, oxytetracyline, spectinomycin, and Lincomycin. These may be in the cattle drug sections since most drugs used on chickens are also used on the other livestock...
Use caution with Sulmet. It can be very hard on chickens' kidneys. It also is not the correct antibiotic I would use. I would just stick with the eye ointment. Do you think the swelling and redness around the eye could be a respiratory disease? It does look very red like pecking, but just...
Feed her some scrambled eggs and tuna to boost her protein. When she is feeling better you could also think about worming her (Valbazen or Safegard Liquid is good.) While she is put up check under her vent and all over for mites or lice. Hoping she gets better soon. Can you get antibiotics...
If the eye is red and puffy you may need to put her in a crate in the coop so they don't hurt her more. Once they see red, they will keep pecking it. Keeping her cage in the coop or run with the gang may keep her place in the flock while she heals. If it won't get into the eye you could use...