I don’t know much about this item But this is what I found on it:
The beret is made by Sheldon M Kasman Civilian & Military Attire, and has the Scots Guard insignia pinned to it.
The Scots Guards claim descent from a regiment raised in 1642 by the Duke of Argyll for service in Ireland. They became the third regiment of Foot Guards in 1661, following the Grenadier and Coldstream Guards in precedence. During the Crimean War they were known as the Scots Fusilier Guards. In 1861 it had twice as many Englishmen as Scotsmen in its ranks. The regiment recruits from throughout Scotland but still includes a large contingent of Englishmen. The regimental headquarters is in London but the regiment is presently based at Aldershot.