If things work out well you are going to get BGJDs from this pair, which are not terribly valuable - there are tons of those for sale as byproducts of EBJD breeding projects.
To get EBJDs you'll have to inbreed your F1s, which is not ideal. A better plan is to pair the EBJD male with an unrelated BGJD female, or get a pair of unrelated BGJDs.
So I guess what I'm trying to say is that you are really paying for the male EBJD, which may or may not be a good breeder. Not sure how things are in Canada but $300 sounds rather steep....