You might be right about those molds being extinct - thought I heard that somewhere else now that you mention it. That said, it wasn't an overly sophisticated design and I'd wager still cheaper to recreate than building something new from scratch. The cardboard inserts were pretty cool, but not necessary. I only display a few of mine with the inserts in, as I want to see the figures behind them.
From an interactive features standpoint, the Death Star had the following:
Swivel Gun chair with pop-off "exploding feature"
4 levels of play
Working elevator with rotating door and ability to lock at each level
Retracting mid-level floor section
Swinging rope accessory
Trap door to access Trash Compactor
Trash Compactor with working door and adjustable wall
Peg holes on each level for figure stability
Pack-in Dianoga figure & foam
and those nifty cardboard graphics inserts
That was $18 at retail. Using a similar rate of inflation/margin creep for the figures ($1.99 then vs. $8.99 now), a similar playset should retail in the $85 range. I would absolutely pay $80-90 for a remade version of this playset. The new FO playset is around $200, so my expectation is that it's about 2.5x as cool as the Death Star. If not, then they should have just remade the classic.