Hi Grant, nice to see your message and I'm sorry you have lost your parents
You have been very lucky to have boxes of information to go through
, it's amazing how much info you can get from these things, don't forget to look at the back of postcards, letters, photos etc. as there is often info there that you might miss. If you have albums of photos be careful to look at the back of those photos but be careful when you remove them. This seems obvious but it's surprising how many photos I have that have been torn off the album hiding all the important stuff. I found my dad's leather WW2 personal hygiene case, he was an officer and they had such things. Inside a tube was his dog tags and a note. You never know where things are hiding, check for secret compartments!
I'm not sure how to check the details of the presentation of this jug but the National Archives have just released some information on railway workers, it came up on my email from them as I registered with them and I get newsletters.
http://www.nationalarchives.gov.uk/records/research-guides/railway-overviewIt might be worth pasting this link and seeing what they have. Also as Mazi said, Railway Bill was very helpful and the BTPHG
http://www.btphg.org.uk were also helpful.
It goes without saying that in my experience everyone on Rootschat is very helpful!!
Sadly I don't think your Wilkinsons and mine are closely related as my family originate from Ticknall, Derbyshire and came to London through the Army, (2nd Life Guards, John was at the Battle of Waterloo) and then he joined the London and Birmingham Railway eventually based at Linslade, Buckinghamshire. Linslade was later, in 1963, to become famous for the bridge where "The Great Train Robbery" took place.
My only other suggestion is that the National Railway Museum in York might be interested in your find. If you photograph it and send them a picture who knows it might interest them.
Good luck with the family history and have fun using Rootschat.
Diane