don't you need to sleeve the outside of a round blade in order to have it fit your crown? I have seen a discussion of these forks recently, I think you can still find the blades occasionally.

The plug style dropouts are a bit of a thesis. You have to find a point on the taper of the blade where they fit inside. So with the dropouts you have chosen, you will have to cut some part off the small end of the blades. You can also mount the dropout in a lathe and reduce the size of the plug. I have done this and it works ok.

I am not familiar with the fork you want to use. If it is not required to rake the blades, I would use constant diameter tubing and use plate style dropouts like is generally done on segmented mtb forks. For example, see this post The finished blade is in this post