I was at a gun show this weekend and there was a colt 45 auto they called a 1911a-1 with s/n 52233 on the right side that had a curved main spring housing with landyard loop at the bottom, The finish was high polished blue with rear adjustable target sights. I cant remember what type of trigger it had. Does any one know the year of this gun and what it is? They wanted a little over $500. for it. Thank you.