The realization space is
  [1   1   0             x1 - 1   0   1   1                 0             x1 - 1                 1                 1]
  [0   1   1   -x1^2 + 3*x1 - 1   0   0   1   x1^2 - 2*x1 + 1   -x1^2 + 3*x1 - 1   x1^2 - 2*x1 + 1   x1^2 - 2*x1 + 1]
  [0   0   0                  0   1   1   1                x1          x1^2 - x1      -x1^2 + 2*x1                x1]
in the multivariate polynomial ring in 1 variable over ZZ
avoiding the zero loci of the polynomials
RingElem[x1, x1 - 1, x1 - 2, x1^2 - 3*x1 + 1, 2*x1^2 - 4*x1 + 1, x1^4 - 3*x1^3 + 4*x1^2 - 4*x1 + 1, x1^2 - x1 + 1, x1^3 - 2*x1^2 + 3*x1 - 1, x1^3 - 2*x1^2 + x1 - 1, x1^4 - 3*x1^3 + 3*x1^2 - 3*x1 + 1, 2*x1 - 1]