What model is the original HDD?
Does it remain spinning after clicking, or does it spin down?
If the scope really needs to see the original model, there are free DIY methods to make a WD HDD look like other makes and models. You may even be able to use a SATA HDD with a suitable PATA-SATA bridge PCB.
Edit:
After reading the manual, it appears that the original drive was a 170MB model. Those were CHS drives. Later models use LBA mode.