You may find that the wiper blades and arms are manufactured by “Anco”, a US based truck and auto parts supplier.
On my pilot house Nc39, 1994 built, I have tracked these down as:
Anco Wiper Arm – stainless steel – part number 44-01.
Anco Wiper Blade 15 inch – Stainless steel and rubber blade – 51-15.
I have not found a UK based supplier of Anco parts. Has anyone else been lucky? UK based Amazon and eBay sites do not appear to stock them and sellers on US eBay were not willing to mail outside of the US.
The suppliers I have found in the USA are Woodys Auto Supplies or Ryders. However the delivery and handling prices to the UK are the killer, doubling the price and this is before HMRC add import duty and VAT!
Hope this helps
Schuss of Beaulieu, NC39, #021