Rhodes is usually low carb, it's a grass hay; we don't have Rhodes in the states, so I can only guess it's lower in protein than Lucerne, since it's a grass hay.
Lucerne is usually low carb, it's a legume, and has good protein and calorie level. However, some laminitic horses are sensitive to it, so just be careful and use it sparingly.
Do no use oaten, wheaten or barley hay for a laminitis prone horse, all have too high a carb level and could cause a major episode.
Beet pulp is a safe calorie source for laminitic horses. I believe in Australia you have access to Speedibeet, micro-beet and fiber-beet. I know speedibeet and microbeet are just beet pulp products, I don't know if fiber-beet has other additives. Beet pulp should be soaked, for one it usually makes it more palatable.
The Maxi-soy is safe for laminitics, but might lack something she needs. [I can't get soyhull products here, so really don't know that much about them, other than they are pretty safe to feed.]