ADHD Medication (Concerta)

After a lifetime of being told I was lazy, I came to university abroad and discovered that I have ADHD and the meds have changed my life. But where I am the process is extremely expensive and bothersome for an international student. I checked most Pakistani pharmacies online hoping I could buy in bulk when back home. But the only thing I've found is Ritalin which doesn't work well for me and requires multiple doses a day because it is not slow release. I am currently on Concerta 36 mg. Is there anyone here struggling with ADHD who has managed to find a way to get Concerta or a drug that's similar?