The realization space is
  [1   1   0   2*x1 - 1   0   1   1          0      2*x1 - 1      4*x1 - 2      2*x1 - 1]
  [0   1   1     x1 - 1   0   0   1          1        x1 - 1      3*x1 - 2      3*x1 - 2]
  [0   0   0          0   1   1   1   2*x1 - 1   2*x1^2 - x1   2*x1^2 - x1   2*x1^2 - x1]
in the multivariate polynomial ring in 1 variable over ZZ
within the vanishing set of the ideal
Ideal (-64*x1^8 + 320*x1^7 - 640*x1^6 + 672*x1^5 - 404*x1^4 + 140*x1^3 - 26*x1^2 + 2*x1)
avoiding the zero loci of the polynomials
RingElem[x1, 2*x1 - 1, x1 - 1, 3*x1 - 2, 2, 2*x1^2 - 1, x1^2 + x1 - 1, x1 - 2, 2*x1^2 - 2*x1 + 1]