The realization space is
  [1   1   0   0   x1 - x2     x1 - x2   0    1    1   2*x1^2 - 3*x1*x2 + x2^2       x1 - 1]
  [0   1   1   1        x1   2*x1 - x2   0    0    1            2*x1^2 - x1*x2    2*x1 - x2]
  [0   1   1   0         0     x1 - x2   1   x1   x2           x1^2*x2 - x1*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 - 3*x1*x2 + x1 + x2^2, x1, x2 - 2, 2*x1 - x2, x1 - 1, x2 - 1, x1 - x2 + 1, x1 - x2, x1 + x2^2 - 3*x2 + 1, x1^2 - 3*x1*x2 + 3*x1 + x2^2 - x2, x1^3 - 5*x1^2*x2 + 3*x1^2 + 4*x1*x2^2 - 3*x1*x2 - x2^3 + x2^2, 3*x1*x2 - 2*x1 - x2^2, 2*x1^2 - 4*x1*x2 + 2*x1 + x2^2, 2*x1^2 - 4*x1*x2 + x2^2 + x2, x1^2*x2 - 2*x1^2 + 2*x1*x2 - x2^2, 2*x1*x2 - x1 - x2^2 + x2]