The realization space is
  [1   0   1              x1 - 1   1   0             x1 - x2   1         1   0              x1 - 1]
  [0   1   1   -x1*x2 + 2*x1 - 1   0   0                   0   1   -x1 + 1   1   -x1*x2 + 2*x1 - 1]
  [0   0   0                   0   1   1   -x1*x2 + 2*x1 - 1   1        x1   1          x1*x2 - x2]
in the multivariate polynomial ring in 2 variables over ZZ
avoiding the zero loci of the polynomials
RingElem[x2 - 1, 2*x1 - 1, 2*x1*x2 - x1 - x2, x2, 2*x1*x2 - 3*x1 - x2 + 2, 3*x1^2*x2 - 4*x1^2 - 2*x1*x2^2 + 4*x1 + x2^2 - x2 - 1, x1 - x2, x1, x1 - 1, x1*x2 - 2*x1 + 1, 2*x1 - x2 - 1, x1^2*x2^2 - 2*x1^2*x2 + 2*x1^2 - x1*x2^2 - x1 + x2^2, 2, x1*x2 - 3*x1 + x2 + 1, x1*x2 - 3*x1 + 2]