The lightest you will find is the Anschutz 1403. This uses the lighter Match 64 action, and is the predecessor of the current 1903, but with a smaller stock, and a lighter barrel. Weight is normally 8-9lb, so much less than a 14lb BSA Mk II.
Otherwise any lightweight barreled target rifle like an Anschutz 1407 (Match 54 lightweight) or the later 1807 and 1907. or the BSA Mk IV should be OK. One thing that will help is getting the stock to fit; many target rifles, and particularly the BSA Mk II, are much too long in the butt for most women. So there ends up being too much gun infront of their left hand. Shortening the stock brings the weight back, and is generally much more comfortable (especially for loading). my 5ft 4in wife used to shoot an Anschutz 1807 barrel in a 1911 prone stock that had had 1.5in of the butt, and 2in off the fore-end.