June,
Sorry for your loss..
Was your son a member of either the G Scale Society, or the Association of 16mm Railway Modellers? - The latter certainly have members who can help with disposal of a collection, if that should be your wish?
If you want to get the railway / loco's running again, did your Son have any friends who shared his interest in model railways? - Approcahing them, will probably find you someone local who can help you either way?
There is a local group of the G Scale Society who would normally meet at Codsall Wood, and members garden's during the year. - Obviously, not presently.
I would contact the G Scale Society, and they will put you in touch with the South Staffordshire group who meet at Codsall Wood:
Committee Contacts We’ve included some of the most common contacts below but you can find the contact details of all committee members on the Committee page. Membership Journal Submissions Advertising & Trade Contact Form We are always happy to hear from our community of enthusiasts and welcome...
gscalesociety.com
I am sure there will be a 16mm Association presence in the area also? - Anybody have details??