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