full-sloping crown is not that unusual, can't tell if that one is a Haden (I think so) or a Cinelli, but since I'm still in the "Brit" camp on this I'd say Haden. Found on lots of Holdsworths and a few Raleighs among many brands. Yours looks like it is drilled for nutted brakes...if you measure the outer dimensions of the forkblades where they meet the crown (long and short axis) we can probably determine if the blades are Reynolds Imperial (my vote) style or Columbus (Continental) dimensions.