Hello James, There was Handbook No.3 which was produced by Nick Hewitt in 1997. This was basically an update of Handbook No.1 but with an increased number of targets. I think the office still has copies for sale. When I was Director I updated the Messier guide (Handbook No. 2). This went through a few versions. The one you show, which I no longer seem to have a copy of, is (I think) the one compiled by Owen Brazell and updated by Nick H in 1995. I then issued a 3rd edition of it in July 2005 which was essentially the same but with some updates to the text and corrections. In 2014 I issued a 4th edition which is basically the same as the 3rd edition but with different images on the front cover. I think the office still has copies for sale. As far as I’m aware there were no other deep sky handbooks produced
If any member would like a draft copy of my catalogue of every BAA publication ever produced since 1890 I shall be happy to reply to any private email. When eventually finished it will be posted online.
Let me just write that there are a great many published ephemera without any sign of a year indicated, and I hope authors will always date their publications in future for the record.