Dark Blue Beret

[Brent Walker]

Sorry guys, I realize this forum is mostly for badges but I don't know where else to turn. I recently picked up a very dark blur beret made by J. Compton, Sons & Webb Ltd. It also has the /I\ British marking. I originally thought it was armoured corps, it was so dark but once I got it home and compared it to my other armoured corps berets, I realized it is actually dark blue. It also has a leather support on the inside for a badge with vertical lugs. Can anyone tell me what branch this would have been used for? I've searched the net but can't find any conclusive answers. Any help would be greatly appreciated.