A bit of a difficult situation really,
1. You are safe to use the springs, not a lot will happen. They will just bottom out very easily.
2. Most springs from different brands are interchangeable, I have not found any yet that don't change.
3. 120KG springs are the highest you can buy, you are better of getting them from Pro-Jump (they tend to be stiffer)
Also thought I might include that you want to buy 20KG above your weight class, so you would be looking for 130-140KG springs (I don't know if they exist)
Hope this helps
DC