Yes, monitors support scaling, however the quality of the result when scaling by a multiplier which is not an integer is not great - it will not be lossless. ie there will be distortion.
For example, scaling between 3840x2160 (4K), 1920x1080 (FullHD) and 1280x720 (HD) works well.
Resolutions compatible with 1280x800 would be, for example 2048x1280, 2560x1600 etc.
As you are no doubt aware, a pixel can't be split so there isn't a workaround which does not alter the representation of the image displayed. For a chart plotter application this is not ideal.