Mechanical Oil pressure gauge fittings

[russcc]

The SW mechanical oil pressure gauges I use have what looks like a special type ferrule type fitting on the line. See photos of the copper and plastic lines with the fittings installed. I don't believe these fittings can be re-used. Anyone know a source for either the brass or aluminum ferrules ? I have all the rest of the the fittings & parts so I don't need whole kit. Thank you Fordbarners.