OK, I will go along. This is a post war Polish Technical Services dagger. Looks to be nickel plated. Also looks to be original to the period. Here is a link to the world daggers site with an example.
http://www.worlddaggers.com/engine/inspect.asp?Item=211&Filter=GalleryThese were in service from 1952 to 1989. At that point the Polish Eagle was replaced with a smaller eagle with crown on the pommel.
There are a lot of post 1989 daggers that were either modified or sold by the factory. Yours is not one of them Yours appears to be correct for the pre 1989 period.
In the past, some dealers have listed these as "German Allies" dagger from WWII, but it did not exist until 1952 so it does not matter how many swastikas people put on them. They are post war.
As to the materials, The Technical Services and pilots daggers are plated base metal and a leather covered scabbard. Early models numbered less than 16,000 are silver plated, after that, nickel plating. Past that, I don't remember.
