Where can you get repair schematics for daisy model 3030 buffalo bill bb gun?

You may want to start with Daisy, See the link below, See if they will send you a schematic drawing. I've heard that these are one of the hardest air rifles to repair. You could also search the web for "air gun repair." There are independent shops that make a living repairing older air guns.

I found the attached link below.