Specifically, it says "the arms, legs, and head do not have rear armor locations", which means they don't have separate locations for the rear as distinct from the front (like the torsos have).
Stock levels aren't a rules question, but I can tell you Amazon just hasn't bothered ever updating its art for the page. The picture shown there is for the 1st printing, which is long gone (and you're far better off with later printings in any case). I can't speak for a third-party company, but you'd almost certainly get a third printing or, more likely, a fourth printing (the latest, with a green cover) were you to order there, simple because earlier stock has sold out most everywhere else.
CGL always has the latest printings if in stock at their store. Right now the global shipping trouble is playing havoc with restocks, but Catalyst is working to bring in more of everything. Beyond that I can't be more specific.
