I made my own at a fraction of the price. No sewing skills required.
Blackout curtain lining - doesn’t fray as it has a plasticsed coating and is the same stuff as the baa/grow/blackout blinds are made from.
And a roll of ‘stick and stick’ Velcro. That means it’s non sew, both the hook side and the eye side have very very sticky adhesive on them.
Stick a strip of the hook side Velcro along the top of your window frame, as near to the glass as you can get.
Cut your blackout to fabric to fit, and stick the loop side to the top of the fabric.
Stick it up at night, take it down, fold it up and put it away in the day. Doesn’t look any less fugly inside or out than a baa/gro blind and costs very little.
Be gentle pulling it off every day so the Velcro stays attached to the fabric. If it starts to come away you can simply staple it on, which works very well.
Bonus is you can also take it on hols. I just take some masking tape to tape it up with temporarily. Or use cheap foil, which works just as well in a temporary situation.