OK, here is the deal: A good friend of mine offers me to trade my SW 645, which I actually like alot for his Colt 1911A1 made in 1942. The gun has BRITISH PROOF MARKS (BMP)on it, but it is blued, as oppose to being parkerized (I suspect it was refinished at some poit). The condition is very nice, with some holster wear, but nothing else. Is there ainy collectors value in this gun, and how rare were BNP marked 1911s? The gun is accurate and reliable. Input is much appreciated.