You can also just switch to any toon you have in lions arch for the forge or go to WvW and go to the portal to lions arch and it still cost nothing to travel
I got the expensive weapons for the karma converter through doing daily chak gerent (Tangled Depths meta). I don't remember if I got them as drops from the meta, or from opening the caches. If the latter, the meta is an excellent way to get the acid needed to open the caches.