Camel Corps artillery were supposedly dressed like the rest of the Camel Corps. Grey serge frocks, cord breeches, dark blue puttees and helmets with a puggaree. Fair bit of converting needed to get to that from these figures (the puttees are obviously the tricky part).
There are some illustrations showing the odd fellow in traditional R.A. blue trousers with a stripe, though.
For non-Camel Corps artillery all you'd need to do to get away with these would be to get rid of the cuff lace and trouser stripes, give them a puggaree and paint them the same as your infantry (while painting the officers the same as your cavalry). The guns used at Suakin were carried by camels, but they were not of the Camel Corps. So this easier option would be correct for that campaign, but if you want to depict the actual Camel Corps of the Desert Column you have a bit more work on your hands.
I think the Officer in the Blue Patrol Jacket would probably be okay. Haven't seem many pics (and no photos) of those, but they were so ubiquitously and habitually worn by officers during this period that it would be churlish of anyone to question it if they saw it on a model.