Short-time lurker first-time poster here.
Aside from the BBOT stock bridge looking cheesy (which I could probably live with) , I'm finding the stock bridge on my 434 a tad uncomfortable under my hand when pick-playing hooky-style (which I am wont to do often enough).
I've just ordered a GOTOH 404BO-4 from an eBay seller in the USA (couldn't find one in my country, I'm in Australia). String-through or top-load, zinc body and big burly-looking brass saddles. Before pulling the trigger I measured everything on the stock bridge carefully with a pretty good vernier caliper , as far as I can tell the screw holes and string holes should line up. That and the bridge has a nice chamfer on the string-through holes which will hopefully accommodate the BB string angle without having to take a file to the holes.
Here's a link to the Gotoh product page:
https://g-gotoh.com/product/404bo-4/?lang=en
and the 5 string version
https://g-gotoh.com/product/404bo-5/?lang=en
OOh: Late update - just found this review on a US Luthier supplies page:
https://www.philadelphialuthiertools.com/bridge-and-tailpieces/bass-bridges-and-tailpeices/gotoh-404bo-4-4-string-bass-bridge-w-brass-saddles/#product-reviews