Ahh yes. The dreaded break angle. Curse of offsets at the best of times...
OK, then I think the best non-standard option would be the Fender tremolo, since it gives me the second most string length and should have no issues with break angle... due to where the existing route is, the tremolo will have to be even closer to the bridge than where Fender relocated it to fix break angle issues on their modern offsets (even closer than it is on the Squier Bass VI).
Sadly, there isn't enough room for the Faction plate with a Buzz Stop as that would be ideal (not without my learning more woodworking and filling in the existing route well enough for two of the plate's mounting screws to go into).