you cant add products to the cart unless the products exist in the CS-Cart database.
a hybrid store probably wouldn’t work too well, if at all.
If the items aren’t in the DB, how would the cart know how much the product is, or how it is shipped or what the taxes are? How would the cart even know the product name or how many have been ordered?
And even if this information could be sent via a link, you’re just asking to get hacked everywhich way from Sunday. Someone could just hack the url and get free stuff.
There might be a better solution for this. Perhaps a script that mines the pages for data and puts it in a csv.