Greetings everyone.
I can tell you that it was almost certainly from Trinity Congregational, and then United Reformed Church in Reading. The church was situated on the corner of Sidmouth Street and Queens Road in Reading.
I was a member there for a good many years until it closed in the early part of 1980. It ws demolished not long after before Reading Borough Council could list it!
Part of the site is now occupied by Trinity Hall, a student accommodation facility, and it would be good for it to go there if they would accept it. Otherwise, it could fing lodging at the church that I now attend, which is a daughter Church of Trinity.
I must add that I am writing this without any proper authority, but would be prepared to be involved in any negotiations.
I am so glad that you found it Thudders, I wonder how it came to be where it was.
I still have a sale catalogue of the contents of the church, but there is no mention of the plaque.
I also have a photo of the church which is on the front of the catalogue which I will scan and post for you to see, but I cannot do it until Monday.
This should clear up the mystery for you all. Thank you for you concern for it's welfare.