When interacting with vendors the Stage Left named rifle sells for 510 credits, rather than the usual 935 credits you get for all other named items.
I thought this to be a simple category error; 'Stage Left' being marked as an average High-End item somewhere in the game files and sold for that price, but those rather sell for 512 credits so not even that fits.
Buying Stage Left from vendors is (a handful of credits) cheaper than your standard High-End weapon as well:
Hey there @R0CH3LL3!
I'm pretty sure the buy price is correct for this item, since that seems to be what I can see in the in-game store and it's very close to the expected value from other similar items as well but the sell price might be an issue because of how different it is from other named items.
Can you get a few more named items similar to your Kingbreaker in your inventory then open the sell menu again and take another screenshot for us? I'll get this sent up to the devs after that to see if this is something we need to fix.
Hello @R0CH3LL3,
Thank you for sharing this thought and bringing more explanation and images to help us contextualize the issue.
I have gone ahead and reported this to the dev team, so they can have a look themselves.
I will keep this thread up-to-date when more information will be given. 
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