practical engineering problem - washing machine

After sitting for the Fundamentals of Engineering Examination, I bumped into a real-life practical engineering problem at home.

When I started up the washing machine, it was taking in water so slowly it looked more like dripping. I vaguely recalled previously the washing machine also did act weirdly, so I tried adjusting the drainage hose. No avail. If it was not the out, then it must be the in.

We opened up the top panel and located the inlet valve. The worst fear would be a faulty circuit board of a fuzzy logic washing machine, cos that's pretty much beyond DIY. The inlet valve looks something like the diagram above. It consists of a solenoid which will pull in the diaphragm when a current passes through the coil. It's not simply letting water coming in, it involves some pressure differentiate, etc etc. We tested the resistance of the solenoid, no problem. We bypassed the circuit board and passed a 220v ac current through it, no problem. Ended up it was the rubber diaphragm which was worn and torn, causing the solenoid valve not able to produce the pressure differentiate to open up the valve properly.

Now the next problem is, where to find a replacement diaphragm? (I actually have contacted the manufacturer. But why would they help you when they could very well sell you a new machine? See how it goes)