Yes, the Miata rack is quite popular, and fairly easy to get. You might also look into Mustang II/Pinto racks (or clones thereof). Toyota racks from other models (Corolla?) would work as well. In other words, almost any... Depends on your budget, and the width you need to go with your front suspension.
When you say "steering column", do you mean the part inside the cab, or are you really referring to the steering shaft, which connects the wheel to the rack? The steering wheel end of the shaft should work just fine in a Locost. Without seeing the other end, it's hard to say if it can adapt to the rack. However, when ya gets down to it, the shaft is really just small diameter tubing with u-joints as needed. I used 3/4 X .120 wall DOM tube for mine, with u-joints from Speedway. So, hang onto the column for possible use inside your car and the shaft as well. They might work for you, but if they don't it's not a deal-breaker.
And, Welcome to the Forum!