Good Day Sockguy,
I'll answer a couple questions which so far have remained relatively untouched.
Socks cannot be purchased through the military as the supply system has eliminated cash sales. The only exception is selected socks produced by Logistik Unicorp which make up part of a Member's Dress uniform (i'll explain further below)
Military members are issued a multitude of different socks, depending on your duties/postings/or element (Army/Navy/Airforce).
I'll break it down to the different sock systems:
Goretex Sock System : Is issued to Army Personnel, Members posted to Army units, or Members deployed in support of Land Force Operations.
Initial issue consists of : 5 pr Heavyweight Grey Wool socks, 5 pr Midweight Green Socks, and 5 pr Black moisture-wicking liner socks. The Life-cycle of the socks, upon being issued, is probably 6 months as mentioned previously. More info on this Sock System can be found at the CTS Website
http://www.army.forces.gc.ca/Chief_Land_Staff/Clothe_the_soldier/hab/2/262_e.asp
Some DND Clothing Stores will issue a member new socks (or any next-to-skin items) every 6 months or so (depending on the life-cycle of the item) and some DND Clothing Stores want the members to bring in the old worn out socks, and exchange them one-for-one/pair-for-pair
Standard "Socks, Wool, Grey" : Issued to all CF Members. Initial issue of 5 pr. These socks used to be one for one exchange (I do not know if clothing stores still stocks these socks) Members can now get a free issue of these socks through Logistik Unicorp's Website, utilizing Logistik's point system.
Black or White Dress Socks : Issued to all CF Members, Initial issue of 5 pr black socks for all elements, Navy may also sign for 5 pr white dress socks to go with their white dress uniform. Exchanges of these are the same as above, through Logistik Unicorp website using the points system.
Socks, Deset, Tan : Issued to members being deployed to arid regions. These socks are one time issue, specifically for deployment (socks may be exchanged in theater of operations if avail.) Worn in conjunction with desert boots or the Tropical Dress Uniform. Initial issue of 5 or 8 pr depending on operation.
Goretex Liner : Goretex Shell for Mucklucks (winter boots). Last ones I saw were manufactured by Mustang Survival. Initial issue is 1 or 2 pr (not exactly sure) These socks are one-for-one exchange only.
*please let me know if i missed any, i've issued many a sock, they all start blending together....
*
I have not seen any of these specific socks available commercially (except for the Goretex "Mustang Survival" ones), although I'm sure there is some knock-offs and variants available.
CF Members are told to wear certain socks with certain footwear. Non-issue clothing of any type is usually frowned upon by most units, but is is rare that anybody wearing "non-conforming" socks would get in trouble. With the sand-traps on the combat pants, nobody can see your socks anyways. When Marching, soldiers are usually left alone to use what works.
I personally dont mind the old "socks wool grey", because they come in my size. I'm not all that fond of the Goretex Sock System, because I fall into a size-gap.
Hope that helps,
Eric