Ergo rebuild halp

Ok, I need some ergo rebuild advice (looking at you, Asher). I have a set of Record 10 Ultra levers which function fine except for the finger levers, which shift alright but don’t return to the brake lever. It seems the spring is either displaced or gone completely.
The problem is illustrated by my solution;

Looking at a blowout diagram I can see the spring in question, but it seems it’s contained in the only part of the assembly which isn’t sold separately

Finger lever assemblies go for between $60 and $90 each, however, there’s a guy on BNA selling a set of same generation Centaur 10 Speed levers for cheap. The ratchet is shot but apparently the return springs works fine. From what I can make of the diagram the ratchet isn’t a part of the assembly, so theoretically I could just transplant them into my levers. The only thing I’m unsure about is whether the internals of Record and Centaur are different enough that the parts won’t work together (from what I can find on google the finger lever is mostly identical across the hierarchy).

Has anyone seen this done before?

Cheers,
Jim

A+ for temporary solution.

Pming you now…