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