Since you’re running steam, we’ll talk in the past tense.
A branchline was not a shortline. Which means that, for your operation, there was a possibility of more capital available. So there was a chance there could have been a coaling tower.
A lot of the decision about how much money to spend on end-of-line refueling equipment would be based on how much profit was coming in, and how much was likely to come in in the future.
If you decide your company was “bullish” on this project, and wanted a coaling tower, I’d go with the small classic woody.
But.
If that was not to be, you’ve got some options.
One is to build a ramp, and park a gon of coal at the top. The lucky winner will be tossing coal from the gon, over the gon’s side, into the tender. Which is strikingly similar to what the fireman will be doing later. You CAN’T toss coal from an un-elevated gon up into the tender. What’s nice about this design is it’s simple and will need almost no maintenance and will last about forever. At the end where the gon is parked, you’d likely have wood trestle bents, so that the gon track could be placed VERY close to the tender. For VERY obvious reasons.
The other option is having to coal dumped at ground level, and hoisting the coal up with a bucket. The basic, and likely, version would be a derrick crane:

You’d have to have a place to unload your arriving coal cars, and be able to remove them. That would also have to be near the crane, of course.
Speaking of cranes, your railroad just might have a rail-mounted crane you could use. It would be small. The old Tru-Scale crane (now Walthers?) would work pretty well, though it should be converted to steam: