A Corsair has a much narrower hull, less freeboard, different deck mouldngs etc and is very unlikely to be in the USA.
It looks like a Highlander or a Flying Scot. They were both Sandy Douglass designs. The FS is still a very popular racing boat in the USA; the Highlander less so but still active. The fact that the builder's/sail number is so high would indicate it's a Scot. For a while I thought it may be a copy of a Scot or Highlander, but the roller centreboard was an unusual feature (initially designed many years before by Theo Smith, an almost unknown boat designer who created some of the most historic boats around) that Douglass used on most of his boats but other builders ignored.
You could find out more from
flyingscot.com/ or
www.sailhighlander.org/ The mainsail is from an Shearwater cat, an English design. See
www.shearwatercatamarans.com/#!gallery/c21gz How it got onto that boat is a mystery.
You'd probably be best off with second-hand sails from a Flying Scot or Highlander.