Pycnogenol and grape seed extract are actually the same thing. The term Pycnogenol just happens to be a trademarked name for the product.
Bilberry (European blueberry) does contain flavonoids that strengthen capillary walls. So will flavonoids from other berries, foods and herbs will also work. Rutin in particular is effective for capillary strengthening. Quercetin breaks down in to rutin. It can be found in high amounts in yellow onion skins and watercress.