Peach trees for the Dallas,Or area
The Willamette Valley is a difficult place to grow peaches. Leaf curl and bacterial canker are very difficult diseases that kill trees in our wet climate. There are other problematic diseases as well. There are leaf curl resistant varieties (Frost and relatives, Oregon Curl Free, etc.) available from nurseries. Some might say the flavor of these is inferior but in my experience this reputation is undeserved. However, even with curl resistant varieties, to maximize the life of your trees you will still have to manage bacterial canker and other diseases. We don't know what killed your original trees. Depending on what killed them, it may not be recommended to replant into the same site.