I lost my Helm of the crusader

[Einsein]

Hi there!

Sooo.... I lost my "helm of the crusader". I don't know if I sold it or if I left it somewhere, but either way, I don't have it anymore.
Why it wasn't marked as a quest item is beyond me.
I tried getting it back by using the console. I used the player.additem and tried all of these item IDs: xx000ECB, xx000EC3, xx000EBD, xx000EB7 and xx000EB1. It kept saying item not found or something like that. Is this because it only works with items from the basegame?

Can anyone tell me if there is a way to get it back, or alternativly, if I can finish the quest without it. It would make sense, since it wasn't marked as a quest item, and I would really hate to have to load an old game, cause I would lose to much progress :(

I hope you can help, thanks :)

[𝕙.𝕓𝕒𝕣𝕜𝕒𝕤]

http://gaming.stackexchange.com/questions/143146/how-do-i-get-the-cuirass-of-the-crusader-back

Its about getting back the cuirass but it seems the method applies for the helm as well.

[CullinB]

"xx000ECB" : "xx" is your Knight.esp's Load order number

Sample (this is my current games)--
00 Oblivion.esm
01 TamrielTravellers.esm [Version 1.39c]
02 Kvatch Rebuilt.esm
03 Mart's Monster Mod.esm [Version 3.8b1]
04 Jog_X_Mod.esm
05 Knights.esp
------------------------
This case Knight.esp's load order number is "05" so replace "xx" with "05"
open console then type
player.additem 05000ECB 1