Nearly all profiles show Plagis’ Spitfire with a newer Vokes air filter.
Like this one which Gaijin have used when the plane was first added.
Or this promo picture for the Plagis’ Spitfire pack.
https://www.iwm.org.uk/collections/item/object/205089833
Here is a picture of No.126 Squadron commanded by Plagis. The Spitfire in the front is not his, but it is also a part of the squadron (it has the Vokes air filter)