Geoff
With regard to Allen G Russell. He would have been 14 years of age when the conflict began. I have found a A G Russell serving in the Cape Police district 2 who also served in the BSAP. There are medal rolls for this chap. However, I am uncertain it is your relation due to his age. I know young men did lie about their age, this would put your relation between 14 and 17 during the conflict. Below are the A G Russell's which maybe worth further research. However, I am airing on the side of caution regarding them being connected to your man in your original photograph.
A G Russell
1253 Cape Police District 2 / A G Russell 1131 BSAP
We also have :-
AG Russell 31119 - 96th Company Imperial Yeomanry ( Metropolitan Mounted Rifles ) raised in 1901.
P,ease Note :- You can rule out this chap , he is Albert George Russell born in Southalk , London.
A G Russell Imperial Railways
A G Russell 370 Natal Royal Rifles
A G Russell 13600 41st Company A S C
I am still looking into the uniform and belt configuration. It maybe post Boer War. I know the snake belt arrangement was used in cadet forces circa 1906/08 and then again in WW1 ref British and Canadian regiments. I am hoping that fellow forummers can assist with the uniform, belt or hat. If you have a look on Google, ref snake / swan belt buckles, there are some interesting posts on the design and history which covers Policing, Masonic , Cadets and Military.
Regards
Dave.....
You only live once, but if you do it right, once is enough.
Best regards,
Dave