Hmmm.. My 2D knowledge is a bit rusty, so I had to crack open the MM.
The HP blade limit is 261%, and is the only item that looks to me to be covered by creep. I seriously doubt they would release that engine back to you without a new turbine wheel, especially at 250%.
The difference in O/H here would be that you'd be up for a new turbine wheel in that second engine. How much? It's been a very long time for me and I would have no idea how much it is worth now days.
As RVDT says, approach your TM FSR and straight out ask them the price of two standard O/Hs, plus the price of a new wheel on one engine.
Are you PBH? Or is the asset owned?