I found it as Gundam Astray, so far I've only found it in 1:144 and 1:100. I've only recently started watching anything Gundam with Gundam Unicorn because it was on Netflix. Always been a Mechwarrior/Battletech fan. Nah, it's an Eva unit. :D
Couldn't look much because work, but yes, it looks like besides the actual standard Bandai kits there isn't much for the Astray (which surprises me, Bandai has pushed Gundam SEED a lot). The closest i could find was the on the predecessor line to the Universal Unit series, the Assault Kingdom ones, those are even slightly smaller at 80mm so it might work (the new Combined Avatar mini is supposed to be at around 75mm but don't have one to confirm, and the O-Yoroi figure pushes the height even more by having the gun pointing up). On series 3 there's the Gundam Astray Red Frame. Volume 3 #011, reference BAN82954. A quick look showed that they're still relatively easy to get for about $10. You might want to check if that one serves your purpose :)
@jherazob Thanks, that's very helpful. I'll try trawling ebay and the stores I know that carry Gundam kits.