i have a necchi nova bu also. fortunately it came from retired machine repair man & all parts there.
..but here's some links for parts & manual if needed
https://www.sewingpartsonline.com/ne...ine-parts.aspx
service manual ...
http://freenecchisewingmachinefiles...._nova-mira.pdf
do you have the owners manual? these are all free pdf's. great site
owners manual
http://freenecchisewingmachinefiles....ova_manual.pdf