They're available new from multiple sources in Australia. A manufacturer with reasonably good response and willingness to ship internationally is
Hy-Way Sunvisors. Another responsive source, who provide both solid sheetmetal and mesh-type visors, is
AutoCables.
Visors for Australian "R & S" model Valiants fit U.S. '60-'62 Valiant and Lancer.
Visors for Australian AP5-AP6-VC model Valiants fit U.S. '63-'66 A-bodies.
Visors for Australian VE-VF-VG model Valiants fit U.S. '67-'76 "square" A-bodies (all except Duster/Demon/Dart Sport). I need to check with Hy-Way on the difference between their CR9 (listed for Valiant VE-VF-VG) and their CR10 (listed for VF hardtop coupe, which is a '69 Dart 2-door hardtop with Australian Valiant front clip).
AutoCables also has new metal fender skirts, duplicating the factory accessories available from Chrysler Australia, and much nicer looking (IMO) than the Foxcraft aftermarket items that were available in America. The local Australian term for these is "wheel spats".
Spats for Australian R&S Valiants suit American '60-'62 Valiant and Lancer.
Spats for Australian VC Valiants look like they may suit U.S. '66 Valiant, and may also suit other U.S. '63-'66 A-bodies —*some homework will be required on this one. The spats for the Australian AP5-AP6 Valiants won't fit American '63-'65 A-bodies except (probably) wagons, because the Australian cars, including sedans, had fully-open rear wheelwells.
Spats for Australian VE-VF-VG Valiants will fit U.S. '67-'76 Darts and Valiants, and probably also Duster/Demon/Dart Sport.
Another interesting Australian accessory is backglass venetian blinds. Those for R-S Valiants will fit '60-'62 Valiants and Lancers (I
have one on my '62 Lancer). The AP5-AP6-VC Valiant sedan venetian blinds are not applicable to any American cars; the Australian roofline and backglass are totally different. But the AP5-AP6-VC Valiant
wagon venetian blinds will fit American '63-'66 A-body wagons. The VF-VG 2-door hardtop venetian blind will fit '67-'76 Swinger/Scamp. No venetian blind for '67-'76 Dart 4-doors, though; that backglass and roofline weren't used in Australia.