I can't speak to the parts catalog issue, but would like to repeat that you should not expect a replacement element to have those same squiggly sides. It will likely have an angular shape.
On my mom's stove, the original 1949 bake element had coiled nichrome that snaked through clay insulators, all housed in a metal framework. The replacement elements were radiant tubes with a vague, blocky V shape, and integrated heatproof spacers to hold he element off the floor of the oven. My mom was an avid baker and the radically different element baked the same as the original.
You're just looking to replace a radiant tube with another radiant tube, so don't worry about a replacement that's differently shaped performing any differently. From looking at your element, I would guess that there are rests on the oven cavity sidewalls for the front end to perch on. If so, you want to be sure a replacement has the right dimensions to use those same rests, or has the supports as seen on the element in the ebay stove.
If you want to stick with the original part, then ebay is likely your best bet and you may need to be patient. Trying to locate the exact original through parts retailers would likely become very time-consuming, and again patience would be advised.
I have linked to an element that may be a viable replacement, but it's more pricey than the later types. I would take John up on his offer. You won't get a better deal if the linked element is any indication.
[this post was last edited: 5/20/2021-23:59]