I thought the Furan 2 would be the better choice considering your water perameters. How ever since you have the 3X sulfa you can use it. Do a 50% water change run some carbon for 24 hours and treat as per package instructions. Your water so not so far out of spec for the 3X sulfa the it will not be effective and might just get this as it is a good choice for septic infections.
The final option I can offer, if Neomycin is available to you, you can try it. It is best fed to the fish by soaking food for about 20 mins. To prepare fish food, use enough Neomycin to treat 5 gallons of water. Use just enough water to mix fish food and Neomycin. After soaking, pour entire contents into aquarium.
I'm really an expert as far as what meds are available to you so I can only be of limited help in that area.