blinds for pretend velux windows

[interstellar]

Ok, so in our loft roof we have a "velux"stylee window in our loft(so,cheap version of a velux)We need a blackout roller blind but all ones i can find are for real velux windows,and you use a velux code on the window to decide what size you need.I don't have a code and can't get a bloomin blind,so,does anyone know where i can get athis type of blind but just using an ordinary measurment .Many Thanks.

B&Q do a kind of roller blind with a clip that hooks onto the bottom of the window

I have the same problem.... Dunelm sell them for velux though, with a code. I need to get round to taking precise measurements of window and trying to match them up to the ones in Dunelm.

I am assuming that the 'fake' velux companies have produced windows as close to velux measurements as they can.