Random(sort of) Actor Select?

I am trying to achieve some sort of level generation just like in The Binding Of Isaac.
Here is what I’ve done so far.
I have a persistent level, in which there are a few levels placed around, streamed out.
When the play begins, it randomly selects from the existing levels.

The little spherical objects are teleporters and all of these teleporters are placed in my persistent level.
Let’s say I make it by hand, that Teleporter 1, moves the player to Teleport 2.
When we press play, it randomly chooses from the available levels, and if level 2 is not loaded, when I use the Teleporter 1, I will end up in nothing. This is not okay…

My main problem here is that I don’t know how to set the teleporters to match the chosen levels.

Basically what I want is to modify Teleport1 destination to one of the streamed chosen levels, and if destination is not streamed(not chosen by random), destroy teleporter actor.

Any help would be great!

PS.: I will be having hundreds of these levels, so creating hundreds of variables is not an option…