I'm sitting at about 423 and until I have a ready supply of Frozen Orbs, I'm in no rush to push it any further. I've already made both of the rare pieces that were an upgrade for me (gloves and boots) and beyond that, I'm a ways away from tanking heroics on a regular basis and even my dps is not quite where I'd like it to make them my bread and butter.
I've got about 13 Arctic Fur in the bank and wrist augments are still orange for me. Most of my leather has come from cruising Sholazar near the Nessingwary camp and skinning the mountains of rhino/cat corpses people leave behind, but I'm still always running short.
I don't see too many patterns requiring 450 skill...I'm assuming those will be later on in the expansion or at the very least, will produce gear that I won't "need" for some time. My realm has already seen its first grand master leatherworker (when he links his recipe book in chat, it says, [Realm first! Grand Master Leatherworking]).
I'd say either set aside some serious time and skin what you need, or set aside leatherworking for a bit until the market cools down and prices are settled to more reasonable levels. Give it a month or two and then plot the route to 450...there will be a lot more information and it'll cost you a lot less.