I just sold my stock spoiler on craigs list, that and EBay may have some used spoilers.
You may want to consider an aftermarket lip spoiler in place of the stock.
http://www.ebay.com/itm/TOYOTA-SUPRA...sories&vxp=mtr
This is the spoiler I put in my car. This seller has other styles as well.
http://www.shineautoproject.com/
Shine auto has a good selection to choose from. May want to consider the spoilers they have.