@Herrgh
I know you said no LPVO … but something like a Vortex crossfire 1-4x24 would look great ( maybe spray the mount/mounts olive ) , these arent much more money really than a top end ACOG replica (uk price) and you’d have an absolute bulletproof (pun intended) warranty for life too , even if it got shot out they’d replace it . At x1 you can use it both eyes open like a red dot and at x4 gives you that bit more reach like the ACOG would . Also not much bigger than an ACOG , twice the eye relief and you could leave your BUIS in place .
just a thought !