Help! My KH190 has broken down.

I have a Brother Electro knit KH190 but the pattern cards slip and it is getting worse. I have taken the unit out and cleaned it but the problem is no better. I can not find anyone local who can fix my problem so I am hoping someone out there can either sell me another part or suggest how I might be able to fix it my self.
By the way, I love your mag and dive in to it as soon as it drops through my letterbox. I go straight to the patterns to see if there are any I would like to try. Pity there are not more bigger sizes though.