I have a 2 foot section of my sill plate that is questionable. House was built in 49, single story on a crawl space. The plate is 2, 13 foot boards. Only the left side board is damaged. (actually 2 feet of the left side is damaged not the entire board). The joists, etc are very accessible. What is the approx. cost to replace this one section of board if I hire someone to do it? Any info would be appreciated.