Re:
I recently built a frame out of Reynolds 853. The weight depends on which tubes are chosen and how they are joined and how much paint is applied. It is now built into a bike and I did not weigh the finished frame on its own because I was not that that bothered. It felt light enough for a steel frame.
Reynolds list about 80 different 853 tubes (different profiles and thicknesses). I think that this is a much greater range than was available for 753. 853 is similar in strength to 753 so it would be possible to make a frame of 853 that weighed the same as one of 753 by using tubes of the same thickness. With 80 different tubes available it is difficult to come up with a typical weight for an 853 frame, some are much thicker than others for the same external profile. Joining the tubes adds weight, welding being the lightest with lugs and fillet brazing being heavier depending on the amount of material used.
Chrome plating is supposed to cause something called hydrogen embrittlement, which I don't understand but do not like the sound of. Reynolds make three grades of stainless steel bicycle tubes, 953, 931 and 921. A better option, rather than chrome plating, is in my opinion to use stainless tubes. You could for example use 921 chain stays and fork blades with an 853 frame, with stainless steel dropouts and possibly stainless lugs. This avoids the extra weight of a layer of chrome or a layer of paint. 953 is about twice the price of 853 but 921 is similar in price to 853 so could be substituted in an 853 frame without increasing the price too much.