C&C Can't find any 9x9 grids?!!!

The only grids I could find are the 8x8 and 5x5 grids. Right now my guinea pigs are living in a play pen that I keep open because they're very tame and love free ranging and leaving the cage whenever they want, they never wander anywhere past the living room, but of course I close it up when I leave and am not able to supervise. So anyways I put the 5x5 grids against the wall and the 8x8 grids on the outside. I know it's dangerous that guinea pigs can get their heads stuck but the only time they ever try to stick their head through grids is when eating hay. I personally know my guinea pigs won't just randomly stick their head through a grid. The only time they will ever stick their head through is for hay which I'll fix with extra bars from the play pen to make the space smaller where the hay rack is to prevent them from sticking their head in there. I was probably gonna put the walls 6-8 inches high around the cage as well. My guinea pigs are pretty tame and doesn't try to bite and stick through grids. And btw I think the fact that they have a huge cage and have "almost" 24/7 access to floor time they tend to not try and escape.

heres how the grids are set up