ASA STILES- 22nd Iowa Reg.-Civil War

I am searching for any ancestor of Asa D. Stiles. My g grandfather, Samuel Lane Wheeler, served with Stiles in the 22nd Iowa during the Civil War. They corresponded frequently after the war. I have a copy of a letter from Stiles to Wheeler dated Septmeber 24, 1902. Stiles was then living in Salon, Iowa. I hope to find someone who may have copies of Wheeler's letters to Stiles. I would love to exchange copies.