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