Good Afternoon Gents
I, as a former member of the RHF, can confirm that the image is of a Royal Highland Fusiliers Tam O'Shanter (TOS).
The hole that you mentioned, in one of the comments, is for the White Hackle.
There should be no other holes in the TOS as the RHF did not wear a capbadge in this form of headdress. They did wear a capbadge in the Glengarry.
There was no wire in the TOS. The use of starch and a good iron was all that was needed to keep the shape.
If you have any other questions regarding the RHF I will be happy to answer them.
Regards
24858229
WO2 WORRALL
RHF 1990 - 2014