Due to all eldritch obelisks either being destroyed or already looted the pearls are next to impossible to get unless you are insanely rich or want to use 15 days to vote for one. I suggest adding a recipe to make them for instance 1 nether star 4 eldritch eyes and 4 void putty / void metal.
The thing is that when you make a custom obelisk portal it screws up big time, a better idea would be to use the farmworld obelisk and use all the arcane arts at your disposal to reach the nearest unraided dungeon.
Cubelex_YT I had the idea of that originaly as well but tests in creative show that you just get teleported into the void unless you place it etc a place there is already an obelisk
This void is still in the same dimesnion as the dungeons, and therefore you can get to unraided dungeons this way