Need help identifying PennCo hardware

We live in North Myrtle Beach, SC. We bought a new home May 2008. The part that attaches to the bottom of the lower window is no longer attached to the window. No one I've spoken with in North Myrtle Beach has ever heard of PennCo and can't find replacement parts. I've attached pics and am trying to locate the parts and find out if they could be installed by someone that replaces parts but doesn't know PennCo windows. I have 2 regular size windows (3050) that needs only 1 side replaced, 2 regular size windows (3050) that needs both sides replaced and 2 smaller windows (2030) that needs 1 side replaced. These are all single hung windows. Any help you can provide we be greatly appreciated. Debbie