I have no idea what this is worth, so I will let the market decide. It is a First Day Cover, with a stamp depicting Rowland Hill, founder of the Post Office (now debased to Royal Mail.) It was issued by the Didcot Railway Centre and depicts a Great Western Railway sorting carriage, so it may be of more interest to railway buff than to a philatilist.
I AM DOWNSIZING MY LIBRARY OWING TO ISSUES OF SPACE.
POSTAGE IN UK: £1. PACKAGING RECYCLED AND SECURE.
PLEASE LOOK AT MY OTHER LISTINGS.