What's the beam?
The hull form was sold as the "Seasafe" before it beacme the Attaque. (well, certainly at 5m length / 2m beam - I got that info from Humber). Not sure if it's just the way it's been antifouled, but there appears to be a similarity in the spray rail arrangement to my 1984 vintage 5m / 2m beam) hull.
If it's got a serial number, give Humber a shout - Sue there was helpful when I was trying to figure out what mine was.
Also assuming you are planning on buying it and have a 4- stroke waiting for it, just beware that the mid 80s transoms were only rated for light mid 80s design engines.....