You can get a rolling chassis from an SR5 for $500 maybe lesser, then go to a junkyard get a 4ag from a ae92, geo storm or MR2 aw11. Then use the supra celica's rearend, hit the for sale forum club4ag for the tranny or junkyard for a 5speed SR5 tranny or strut caseing for a DIY coilover add a supra wheels then you got a legit AE86. Trust me my friend did this took him less than 3months to get it running, registered and on the road.

some KE70 are in fact AE70, they have the 4AC like an ae86 sr5, rack and pinion like AE86 and share almost everything with AE86, this can be found under 500$

a guy here in Canada sell one KE70 and one AE70 for 400$ for the two... you can find that kind of deal on your side of the border