By RAW, a Rune of Contingency would take 147 days, and 73,500gp to inscribe!
So, in essence, it's completely useless. Has anybody else house ruled an alternate version of this Feat? Would a fairer estimate be comparable to scribing scrolls?
https://www.d20pfsrd.com/feats/item-creation-feats/inscribe-rune-item-creat ion
I would use the Pathfinder inscribe Magic Tattoo feat instead of this one, as it for the current game.
That said, I would consider importing the 3.5 runes as possible choices to use with that feat.
I think that perhaps what you are not understanding, is that it is creating a permanent magic rune that lasts forever. It isn't a one time thing but rather a slotless magic item that can't easily be taken from you. It is more comparable to craft wonder item than scribe scroll.
There are plenty of wondrous items that cost as much as take as long to make. Obviously these are high level items,
Perhaps you should recruit some other crafters to help you shorten the time it would take? There are rules for hiring spellcaster services.