Would help to know which saw this is.
EBAY is a good source of parts.
The OWWM forum is a source as well.
While the old WT saws are cool, I see them show up for sale relatively cheap on occasion, might be possible to buy a complete saw for spare parts.
I picked up a smaller one recently, buying some other tools, guy had a smaller WT saw listed for $25 too. Was really trying not to add to my collection, when he told me it was his grandfather's I couldn't help it.