The realization space is
  [1   0   1   0   1    0   x2    1     x1*x2 - x2            x1 - x2^2 + x2 - 1                    x1*x2 - x2]
  [0   1   1   0   0    1   x2   x2   x1*x2 - x2^2                x1*x2^2 - x2^2                x1*x2^2 - x2^2]
  [0   0   0   1   1   -1   x1   x1      x1^2 - x1   x1^2 - x1*x2^2 + x1*x2 - x1   x1^2 - x1*x2^2 + x1*x2 - x1]
in the multivariate polynomial ring in 2 variables over ZZ
avoiding the zero loci of the polynomials
RingElem[x2 - 1, x1, x1 + x2 - 1, x2, x1^2 + x1*x2 - x1 - x2^2, x1 - x2, x1^2 - x1 + x2, x1^2 - x1*x2^2 - x1 + x2, x1 - x2^2 + x2 - 1, x1*x2 + x1 - x2^2 - 1, x1^2*x2 + x1^2 - x1*x2 - x1 - x2^2 + x2, x1 - 1, x1*x2 + x1 - 1, x1^2 + 2*x1*x2 - x1 - x2, x1 + x2]