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