Places to look for marks.
Pull off the fore stock look under barrel and in the barrel channel. Also look on the action face. If there is any dirt or debris on the front of the action, use a piece of wood like a tooth pick to scrape it away and see what might be hidden.
Pop out the breech block and look on it especially on the top for a very small mark that might even look like nothing more the a small pit or scratch.
Indeed there be may no markings. The markings can be very inconspicuous. The markings in the picture below appear on my Westley Richards 1871 patent rifle. The marking is less than 1/8 of an inch long and says Bowler...well all you can see is "WLER" I have had the rifle for about 5 years and have looked for the mark a number of times and only found it last week when some one else told me what to look for. I just recently learn that Bowler mark is seldom seen as a full mark.
You have two numbers that might be clues to identify this rifle. A letter to Bester might put you on the right track.
Personally I think it part of the large number of rifles sold to the Boers prior to the second Anglo-Boer disagreement.
One thing not commonly reported is that the English intercepted a number of the weapons destined for the Boers and turn them over to the Town Guards and other civil Militia. My Made especially for ZAR Rifle is marked faintly on the butt P.E.T.G. Port Elizabeth Town Guard.

Marks can be easily hidden by patination.
I advised a collector in SA on how to properly clean an old Martini he acquired years ago in Zululand. The dark old linseed oil had turned the stock almost black. After some careful treatment, the marks showed the rifle had belonged to the 80th of Foot.

Of course your vicars rifle may be, beyond the two numbers, mark free.
Yes I do get a bit passionate about these rifles.