FinnurE said:

The Workprint to fill in anything still missing on the sides of the frame

I have a certain sympathy for Stotaro's point of view, but understand why you might wish an OAR preservation. Unfortunately, I think taking a blu-ray source for most of the image and filling in the sides from another transfer would be a bad idea. The transfers would probably look very different in color and detail, and I don't think the result would make for pleasant viewing.

You'd be better off transferring that 2.35:1 VHS to DVD, cut or not. It might not look great, but at least the image quality would be consistent and it would be worth watching for fans as a genuine preservation, like the Puggo Grande.