Where can I buy higher density expanding foam?

Looking to buy 4 or 6 lb expanding polyurethane foam in Canada. I can find lots of 2 lb density but look for more density. Hoping to not have to order out of the USA. Does anyone know of a marine shop in Canada that might have this?
Thank you

 

Maybe try outside of marine suppliers? As a buoyancy foam, anything over 2lb is considered "too heavy", and not much used in boats, because of that and the additional cost, but it certainly is far more durable and resistant to water intrusion. I'd be amazed if you could not source it in Canada, it is available where I am, and you can buy sheet foam of 4lb density which is called "hard foam".

 

Noah’s in Eastern Canada may have it