$500 for both is a good deal despite the poor BGs.
Be careful (like ZNET states) when dealing with the drop down Balls on BaB,
even when swinging the light box baffle open/down,
to gain front access to the balls and bulbs in the LIGHT BOX/BACKBOX.
You can expect to spend $250-300 per BG from either WEBB or bgresto,
You might be able to find a NOS or decent used BG for $100-200.

Quick question, how do you like the dual flipper action on showboat?
Do you find it confusing?
One can always rewire the flippers to either flip alternately or simultaneously.
By that I mean if you hit the left side flipper button, it activates both (right facing) flippers and visa versa.
Or wire it so when hitting the left flipper button it fires both flippers simultaneously
on the left half of the playfield and
when hitting the right flipper button it activates both flippers on the right (half) side of the PF.
I know that Tim Arnold of PHOF has done this rewire hack.

Not a wedgehead but Flying Chariots is right up there with those two gameplay wise.