Looking at the image showing the parts on the Daemonscape E-bay listing it looks to be 12cm long, abot 5cm wide at it's widest (9cm if you include the wings/missile mounts). Eyballing from that and the other pics, maybe 5cm tall at the tallest part (excluding landing gear).
It would probably make a decent 'Landing Craft - Tank' at 15mm scale - I'd want to block in the canopy with plasticard or similar and put a 15mm scale cockpit on it somewhere, but ymmv
Daemonscape Ebay link:
https://www.ebay.co.uk/itm/125459515347?hash=item1d35f847d3:g:uS8AAOSwQH1i9SS9On a side note - anyone know if the Daemonscape webshop is gone? I could see it fine September, but the past month or so I've been getting a blank page for them.
What I can see on their Facebook page
implies it might be (they appear to putting all their stuff up in their E-bay shop, where previously it was a limited selection), but without an account of my own to post there I can't ask directly.
It might just be time to update my firewall whitelist again.