Drifting analog stick

[CyberClaw]

I bought an Access Controller a year and something ago when I lost my right arm arm-wrestling a highway safety rail at high speed.

Problem is, this over-priced controller for handicapped, is clearly, handicapped as well. Contacting e-Dimensional was met with no kind of reply.
Hard to press sticky buttons was easily fixed (as easy as it can be when you only have one arm, but it was either that, or not playing at all...).
But the problem I'm still facing is a drifting left analog stick. It constantly goes to the right. I've disassembled, cleaned and reassembled the damn thing, but it was of no use. What's my next option? I mean after flying half world to beat e-Dimensional in the head with a very big stick for selling me a shoddy controller?
Is there any way to calibrate the analog stick? Or do I need to get a new one, and solder it in place of the old one?