The closest you could probably get to a sleeper, is to pick up a MkII Supra:
And swapping in a 7M-GTE instead of the 5M-GTE that's in it. However, you'll want to do headgasket and several other mods. It wouldn't be cheap or easy, but it's cheaper than a MkIV.
However, is it worth it? Probably not. You could get 450-500hp, with a lot of work. Is it worth it to buy a MkIV Supra? In my eyes, No. Prices are so horribly inflated it's not even funny.
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1988 Mk3 Turbo Targa - 17.5psi, 486hp, 494tq.
[img]http://www.**********s.com/supra/rsw_sig_stupidTN.jpg[/img]
Who came up with this 500px wide BS?