Just a thought but might they have been POW's together and signed this after liberation. The FEPOW data base is only accessible to members but perhaps someone on here is a member and can check a couple of names.
Had a very quick look earlier as I too thought they might be FEPOWs, but nothing turned up. If you want to check more thoroughly here is a good list (at the moment an index to Japanese Index Cards) accessible to all British FEPOWs Tim
Surely a souvenir obtained by non-POWs. If my uncles (POW) experience is anything to go by, the last thing he would want would be a reminder of what he went through and top of the list of no-wants would be one of their Rising Sun flags.
I have a photo of soldiers with a rising sun flag which they found or captured in Burma. It seems quite likely that yours is something similar. Lots of portable souvenirs were brought back to the UK and what better memento than to get your mates to sign it. Can I suggest you make a list of their names. Did some add their home towns?.Could be a clue to what regiment they were with. Someone here might recognise the names. Bit of a long shot but you have to try everything.
I think I’ve made a possible breakthrough one of the names that I thought was surname Muar then Lahore was a big battle in Malaysia
There are many candidates for Jack Rawcliffe of Preston. Surname First name(s) District Vol Page Births Sep 1910 (>99%) RAWCLIFFE John C D Preston 8e 526 Births Mar 1911 (>99%) Rawcliffe John W Preston 8e 521 Births Dec 1915 (>99%) Rawcliffe John T Hodgson Preston 8e 683 Births Jun 1917 (>99%) Rawcliffe John Airey Preston 8e 715 Births Dec 1919 (>99%) Rawcliffe John Duxbury Preston 8e 860 Births Mar 1921 (>99%) Rawcliffe John Ashcroft Preston 8e 929 Births Dec 1921 (>99%) RAWCLIFFE John J Hallmark Preston 8e 814 Births Mar 1922 (>99%) Rawcliffe John H Hardman Preston 8e 807
Two candidates for L Hall of Rainford, which was at the time in the Prescott registration district of Lancashire. Births Jun 1916 (>99%) Hall Leonard A Ratcliffe Prescot 8b 1390 Births Mar 1923 (>99%) Hall Leonard Walsh Prescot 8b 1398
I do not believe that these are the names of Prisoners of War. Only one of the names comes close and does not appear appear to match the details given of his home town. None of the names, apart from A Bentham, appear in the casualty lists for the Far East and none were members of the Burma Star Association.