An AH wouldn't stabilize the prices any quicker than it would take for it to naturally stabilize. The reason being there's not a ton of people actually making weapons most are actually working on armors and accessories since they're the easiest to make and require only 1 craft unless you want to make EVERY material yourself.
See here's the issue with the "need an AH argument"--it still requires players to create and populate the AH with their items, much like the retainer/personal bazaars as we're experiencing now. Many want an AH but it's not going to instantly solve all our problems, the game's economy is still brand new, it will take time for things to stabilize even in this type of economy.
Even a week later people are still trying to sell bone rings for more than 10k. The people who sell things for reasonable prices will be known and get a lot of the business compared to billy bob who sells everything for 70k-300k no matter if it costs 1k to make or 500g to make.
I don't know if you've played FFXI, but in 2005 I think the gil selling websites sold a million gil for $1, you can guess who long it took for the AH to become worthless when it comes to even HQ items which cost up to 10x less than their NQ equivalent, it took months for it to stabilize and there's still some people today who's swimming in all of the gil they made then. The reason this is, A LOT of gil came into circulation but didn't really go anywhere for the longest, in FFXIV you get like 10-20k per leve and even higher on higher difficulties and sharing/linking with others so a lot of gil is entering the system which is why it may seem like a lot at first it really isn't that much when you realize most people who played since CE has multiple hundreds of thousands of gil and even millions. Once SE throws in gil sinks everything will stabilize much quicker.
An AH would be nice but when talking about an economy regardless the medium it will take time for everything to stabilize.
`Sides, everyone is too busy running around wanting to look like an Assassin's Creed reject to really bother with weapons lol. So it's frustrating but the game is still new once everything gets stabilized it won't be so bad--50k is a lot for someone just starting off and not up to snuff on their leves but in general it's not that much with how much gil you'll end up with very quickly.
Once we get our 100,000g bird rental fee and 300,000 airship fees people won't be able to charge that much for very long.