I have a set(4) of 13x8 three piece aluminum wheels that I ran on my 87 MR2. If I remember correctly they weigh about 9 lbs each, maybe 8. There was another brand(Kaiser maybe?) that was about 1 pound lighter but were notorious for leaking past an o-ring that sealed the 2 halves. These use a bead of RTV to seal the halves. Backspacing is 4.5 inches.
They currently have a very old(15-20 years old) set of Hoosier on them.
I'm in the Denver CO area, so shipping shouldn't be to crazy.
Make me a reasonable offer and they could be yours.