CERTAINTEED WEATHER STRIPPING FOR "NEW CASTLE" WINDOWS

I can't be certain of what you have without seeing a picture of your existing seal's 'end profile', but we've seen some Certainteed Weatherstripping for New Castle windows use a shape similar to our 58-169 or 58-180. We don't have an exact match in terms of how yours might connect to the window the 58-169 has an adjustable nail-on flange, and the 58-180 has an adhesive base. See if either might work for you.