Alternative to ref as input-argument for delegate-functions

Greetings everyone,

I am currently working on my first game, and searching for a generic way to bind a function which increases/decreases a Character-Stat to a button-click: For example my character looks like this:

 public class Character {
     public bool m_rangedAttack = false;
     public float m_attackRangeInch = 8.0f;
 
     public float m_movementRange = 0.0f;
     public float m_wounds = 1.0f;
 
     public float m_numberUnits = 1.0f;
 
     public float m_hitChance = 1.0f;
     public float m_hitDamage = 0.0f;
     public float m_hitNumber = 0.0f;
 
     public float m_blockChance = 1.0f;
     public float m_blockDamage = 0.0f;
     public float m_blockNumber = 0.0f;

     public Character(){
     }
 }

For the character editor I am creating a button (from a prefab) for each of these stats. Now I am searching for a generic way to bind a function to the on-click event. In best case i would like for each button to use the same function just with different captured variables. My current code for this looks like this:

 public class CharaterCreatorScript : MonoBehaviour
 { 
     private Character m_char = new Character();
     
     private void addB(string name, ref GameObject prefab, ref GameObject canvas, ref float stats){
         GameObject button = (GameObject)Instantiate(prefab);
         GameObject plus         = button.transform.GetChild(1).gameObject;
 
         //[ToDo] Make this as generic as possible, ref is not possible due to anonymous function
         plus.GetComponent<Button> ().onClick.AddListener ( delegate {  increaseStat (ref s, 10.0f); });
     }
 
     private void Start() {
         GameObject pf_simpelButton = (GameObject)Resources.Load("Prefabs/SimpleButtonPrefab");
 
         GameObject anchor = GameObject.Find("ButtonListContent");
 
         addB("AttackRange",    ref pf_simpelButton, ref anchor, ref m_char.m_attackRangeInch);
         addB("MovementRange",  ref pf_simpelButton, ref anchor, ref m_char.m_movementRange);
         addB("Wounds",         ref pf_simpelButton, ref anchor, ref m_char.m_wounds);
         addB("NumberUnits",    ref pf_simpelButton, ref anchor, ref m_char.m_numberUnits);
         addB("HitChance",      ref pf_simpelButton, ref anchor, ref m_char.m_hitChance);
         addB("HitDamge",       ref pf_simpelButton, ref anchor, ref m_char.m_hitDamage);
         addB("HitNumber",      ref pf_simpelButton, ref anchor, ref m_char.m_hitNumber);
         addB("BlockChance",    ref pf_simpelButton, ref anchor, ref m_char.m_blockChance);
         addB("BlockDamge",     ref pf_simpelButton, ref anchor, ref m_char.m_blockDamage);
         addB("BlockNumber",    ref pf_simpelButton, ref anchor, ref m_char.m_blockNumber);
     }
 
     public void increaseStat(ref float stat, float max){
         if(stat < max){
             stat++;
             Debug.Log ("Increases to " + stat.ToString());
             updateText();
         }
     }
 }

My current way of using a ref as input for the delegate is not possible in C#. Is there a way to code this, or would i have to define a different function for each stat (e.g. increaseWounds, increaseRange,...), which would have access to my m_char member-variable?