Where to find fittings and stuff?

I'm putting together some dry boxes and would like to use filament pass-throughs like these. This one is from a Sovol/Comgrow SH02 dryer. Anyone know what these are actually called and where to look for them?

Yeah I could print something but these fit really well and I don't have a use for 98% of a flexible spool.

https://preview.redd.it/14398ddy4ang1.jpg?width=960&format=pjpg&auto=webp&s=5b0d3581ce5c2865e6b4da154600b35340c832aa

https://preview.redd.it/odgreddy4ang1.jpg?width=960&format=pjpg&auto=webp&s=f76fdcde178626d93fa39a444032bdb8f873dbc3