That looks suspiciously like an original MRH (Model Racing Hulls) Silak to me. MRH were an Eastbourne based manufacturer of multi race hulls way back, ran by a chap called Graham Pollard...along with the Silak (designed by World Champion Georgio Merlotti and made under licence by MRH), Graham also produced the Kali, Isotope, Mini Silak, and a couple of others who's name escapes me for the moment.
They were superb hulls until Graham sold the business to another Eastbourne based company run by a guy called Tony something...they were never as good then, more's the pity.
Here endeth the lesson...
Rich