Can anybody recommend the best place to get a replacement right-angled jack plug with lead attached? It is a replacement for a brother sewing machine foot pedal.

 

Try ----> https://www.ebay.com/itm/3-5mm-Mono...uAAAOSwRNRbEVDg:sc:USPSFirstClass!40391!US!-1

Or ----> https://www.ebay.com/p/Philmore-70-...m=231722718000&_trksid=p2047675.c100005.m1851

Or ----> https://www.ebay.com/itm/Right-Angl...UQAAOSwzJ5XYD6X:sc:USPSFirstClass!40391!US!-1

together with ----> https://www.ebay.com/itm/Two-6ft-Au...072084?hash=item1a19fba5d4:g:AF8AAOSwL7VWlT-U

 

That cylindrical section behind the sleeve may make generic replacement difficult.

It looks like you may have torn the through hole plating out of the circuit board also.