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