If i knew i would tell you man. Im in the same boat your in although i have found some stuff for my 88 celica gt on ebay... if I find anything else ill be sure to let you know.. i hope you'll do the same.
Rear suspension is shared with the Supra (IRS).
Changing the diff ratio can give you better acceleration by sacrificing top speed.
The good old 22R has plenty of bits from go-fast shops. www.lcengineering.com is one of the most well known if you want ideas.
Putting on a 20R head raises compression, allowing it to be tuned for more power.
A good free flow exhaust works wonders for nearly any engine.
Add a decent cam and you have something with bit of go.
Whiteline and Kings Springs cover the suspension.
Dobsons might have something too.