Stanley goalkeeper Dunbavin, 32, is expected to miss the rest of the campaign having undergone shoulder surgery last week.
Although manager Richardson admits the player's presence will be a big loss on the pitch, he feels the former Liverpool trainee can still be a positive influence around the dressing room.
"It's a long road back for him and I feel for the lad," Richardson told Press Association Sport. "He's had a really good start to the season, probably the best start to any season since he's been a professional.
"In that aspect it's a bit disheartening for the lad, but you've got to move on quickly and Ian was one of the first people to say that.
"He's a good character in and around the dressing room so he can still be effective in that way.
"Although he'll be a miss he'll still be around and it will help him on his long road to recovery."