Hi Steve. Just sold a vgc .177 Webley Omega carbine only this morning in actual fact (the last of four Omegas I had, as have become a Webley Longbow groupiee ), with its open sights for £225 collected, and as I sold a set of original Omega open sights on here, only last week, for £25, and as you intimate your Omega isn't quite in vgc, I would best value your .177 Omega carbine, unseen, at around £150 plus post. Hope this (sort of) helps . Atb: G.