The parts for that target head are discontinued. You could convert it to the newer style Super Spider (thin wall), but that would get costly.
If the machine is working properly now, and the target segments are in good shape, then it might be worth it. However, if the segments were to break/crack, you would have difficulty locating new replacements of that style.
I think you should pass this one up and look for one with the new Super Spider target head.