[Feature Request] selectable pixel aspect ratio in Camera Raw for stills taken with anamorphic lens

I just picked up a Sirui lens with 1.6x anamorphic squeeze. I am using it mostly for stills. Camera Raw does not have an anamorphic desqueeze option. Neither does Lightroom as far as I can tell. In Camera Raw under Geometry there is an "aspect" slider, but it vaguely goes from -100 to 100, and at -100 it only stretches the aspect ratio by about 1.2. And it shrinks the vertical resolution in the process.... Can we please have a proper pixel aspect ratio option that allows you to type in a custom value as a decimal of a percentage (eg. 150% is 1.50)? And if it's stretching the pixel horizontally, it doesn't affect the vertical resolution; and vice versa.