I am not sure this will work, but did you consult an electrician? I have also found alot of parts for my older machines online, just google sewing machine parts. I hope you can save the machine

If it's truly broken and you don't want to put out excessive cost in repairs, you have nothing to lose by taking it apart. There are many generals parts suppliers on the web which may have the transformer needed. I guess I'd do that search first before dismantling. Otherwise taking it apart, is a good lesson in how a machine is put together.