You're asking for a blueprint for a sewing machine and a description of each of the parts so that you can assemble a sewing machine from its individual parts.

Maybe the keyword is assembly instructions?

Although I'm doubtful that those are available to the general public. You might be able to get a copy from a service technician or repair org.

I don't think most companies expect their customers to assemble critical components and still offer a warranty.

The general population struggles with reading IKEA furniture instructions.