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