Rear throttle body feed hose-availability?

My partner's 1.8 litre iO was visiting the local mechanic yesterday for some maintenance work.

The 2 radiator hoses, 2 heater hoses and the front throttle body by-pass hose were all replaced.

The rear by-pass hose is obsolete through Mitsubishi and not available through aftermarket sources like Mackay hoses, Gates etc.

The guy at the spares desk at Mitsubishi was kind enough to give me the dimensions (8mmx350mm).

Has anyone replaced this rear by-pass hose and if so, can a length of 8mm heater hose do the job....or does it need to be the moulded specific part...which is not available? Or maybe another hose from a different application can be utilized....?

Thanks,

Paolo5