The realization space is
  [1   1   0   0   1   1                 0           x2                 1            1    1]
  [1   0   1   0   1   0   x1*x2 + x1 - x2   x1*x2 + x1   x1*x2 + x1 - x2   x1*x2 + x1   x1]
  [0   0   0   1   1   1              x2^2         x2^2              x2^2         x2^2   x2]
in the multivariate polynomial ring in 2 variables over ZZ
avoiding the zero loci of the polynomials
RingElem[x1 + x2 - 1, x2, x1, x2 - 1, x1 + x2^2 - x2, x1 - 1, x1 - x2, x2 + 1, x1*x2 + x1 - x2^2, x1*x2 + x1 + x2^3 - x2^2 - x2, x1*x2 + x1 - 1, x1*x2^2 - x1 - x2^2, x1*x2 + x1 + x2^2, x1*x2 + x1 + x2^2 - x2 - 1, x1*x2 + x1 - x2, x1*x2 + x1 + x2^2 - x2]