Just phone the British legion and ask for a collecting tin to rattle under everyones nose at work.
I did, and grabbed every customer. When they checked my tin they were amazed – first timer and one of the highest they had. Could it be the cheek, the sincerity, or the guilt trips laid on? I did find “You look like the kind of lady who deserves a flower” to be very effective. Kind of a white feather shaming routine, boot on the other foot.