Need assistance on replacing a vintage bridge hum.pickup.

The 70's bass is a rare bird. Hopefully you have something that will work or point me in the right direction. I'm also open to thinking-outside-of-the-box alternatives you may have in stock, if it'll fit.

Cavity is 92mm x 51mm

link below for reference :
https://www.vintageguitarandbass.com/epiphone/catalogues/1971_ET-285.php

Thanks for your time!