Don't recall ever buying new chains for my 4x4s, ATVs or tractors. Bought lots at yard and auction sales though. There is a truck stop that gets a lot of logging business that sells chain parts (crosslinks, connectors) when I need something in a hurry but mostly its a hammer,vise, pry bar and cut-off disk in the grinder. The cross links may be hardened but the side joiner links are soft and bend easy, even better with the special pliers(so I'm told). The long side links last forever and i replace the cross links as needed.
I normally put my chains on my 4300 when the rain starts in the fall (Oct) and remove them in the spring when the mud dries up.