Okay, this is from Donald Featherstone's 'Victorian Colonial Warfare: Africa'.
September 1899
Cavalry (2 Regts)
5th Lancers (Natal)
18th Hussars (Natal)
Artillery (4 Batteries = 24 guns)
13th, 67th & 69th Field Batteries (Natal)
10th (Mountain) Battery (Natal)
Infantry (71/2 Battalions)
1st Royal Irish Fusiliers (Natal)
1st Leicestershire (Natal)
1st King's Royal Rifles (Natal)
2nd Dublin Fusiliers (Natal)
1st King's Liverpool (Natal)
2nd King's Royal Rifles (Natal)
1st Loyal North Lancashire (Cape Colony)
2nd Yorkshire Light Infantry (1/2 batt) (Cape Colony)
So this is what he says were in South Africa before any reinforcements arrived, but there were also some sent out just before or just after hostilities began. You want those too?