Insuman is an isophane insulin, also known as NPH.
Other brands of NPH, which should work about the same are Humulin-N (by Eli Lilly) and Insulatard (by NovoNordisk).
Most people prefer different basal insulins like Tresiba (works much longer, no peak), Levemir (not unlike NPH but less of a peak, slighly longer acting than NPH), or Lantus (glargine), somewhere in the middle between Tresiba and Levemir.
All of them are usually more stable than NPH, which has a relatively sharp peak and shorter action time.
You'll be able to obtain a different brand of NPH without issue, but it might be worth looking into other types of basal as well.