I understand the value of the engine in the eyes of the beholder but I also understand the budget of most people aspiring to the N/A Supra...... genuinely NO offence intended. Let me be clear with my statement. The N/A engine is bullet proof, the only people who pop them are complete idiots who either go out their way to do so or evolution dictates that course. When such a thing happens they will, generally, then look to replace such a beast with a similar power plant for as little money as possible. When presented with a 1k option or a £150 option I can almost guarantee I know which way they are going to go.
All that being said though, the ECU is the real jewel in the crown. With what Jake has said regarding the engine I would suggest that it will be worth FAR more in bits, including selling the ECU separate, than it ever will as a package. If I was looking for an N/A I would be taking the £150 option as I would know that if it turns over and fires up on 6 cylinders..... it's bomb proof!