So I already know this is imposible now, but I really think they should make it possible to craft seeker onto runearms. Few, if any artificers bother with a seeker repeater because the occasional extra crit does not make up for loosing the valuable always damage from a damage prefix. Then you get up to greensteels and its just forget about it.
Meanwhile we have the occasional item with seeker(such as The Bloodstone or Tinker's Gloves), and for melees you can carry a Seeker shield or seeker offhand weapon, and have the effect apply to your mainhand. Meanwhile, us artificers are right out in the cold! Seeker should be craftable to rune arms!
Who's with me?