I don't know if Commandos count as "Special forces" but I can't find a better slot for this photo. Just found it in my dad's things annotated "Commandos Bulford Camp June 1941" - he is second from right, back row. I know he was in 5 Special Service Battallion (later 5 commando). He did early training (Summer 1940 after returning from Dunkirk) near Fort William and Spean Bridge.
Brickmaker, Great photo. If you dont already use it, can I suggest the excellent Commando Veterans Assoc website at: http://www.commandoveterans.org/ There are several peopple there who have family connections with 5 Commando, and an excellent photo board (where your photo would fit in nicely!). Regards Pete