Hi Mark,
I was in London on business and I stopped by J Roberts. They have a few of the original ledgers and I believe copies of most of them. the rest went to Rigby/California and have never been seen again. I have a couple Rigby's and was able to look them both up. Your 5394 is so close to mine; I'm sure that its in the ledger book that i looked at. I would contact Paul at J Roberts as they are very helpful.