Ideas for temporarily blocking noisy street from window?

[StructuredChaos]

We are moving soon, so not a long term issue, but for the next few months we would love to find a way to reduce sound in the bedroom at the front of the house.
It is very well double glazed (newish) but a noisy construction is ongoing across the road. Lots of sounds like pallets dropping and impact, large, deep growling vehicles, etc.

It begins around 6am and due to his shifts this is really messing with DH's sleep. We propped a spare foam mattress over the window and whilst that muffles it a good amount, it isn't practical (it's huge and keeps falling over).
I looked at thick foam inserts online and the amount we'd need is just more than I am willing to pay for short term (£100+).

The window is a standard sash rectangle style as seen on many old row terraces/cottages that have been modernised. Around 120cm wide, can't recall height..

Any ideas?
Are those insulating blinds any good?
Sound tiles?

Are you in the UK? I don’t think construction sites are allowed to start work before 8am, so I’d start by contacting your local environmental health dept and see what they say. Otherwise, I can’t imagine anything you put on the window will block out enough sound. Has he tried a sleep mask with earplugs (Amazon)? And/or with headphones and white noise?

Have a look at theplasticpeople.co.uk for affordable secondary double glazing. They've had very good reviews in the press.