@mwlucas ... spare funds - you're waiting for to go away, because I see few.
Somewhat relatedly, maybe get in contact with Dead Gentlemen. They seem to be making films that fit your genre, have experience with quasi zero budget production, and already have a cult following.
@jens
I haven't investigated for a few years. In 2019 I expected it to be achievable by 2025, but the pandemic scrambled everything and I haven't reassessed.
I wouldn't be surprised if now IS the time.