I do alot of refurb to order for practical commuters ... oftens expats that appreciate vintage , and want a daily commuter
I would go with velo orange. ( personal choice, i just love the way the things they offer are finished/thought through
elite look fine and appear to have dull finish or pig metal tone , which may be more in line with the style of your bike.
I've used problem solvers , and similar above with plastic cut offs
Bear in mind, once you have a bottle in here its not gonna be a very visible feature .
you can also retro fit a brazed and tap solution. that's the most elegant ..... or find some flexibility between location ( downtube vs seat tube, versus rear of saddle mount used by tri athletes. )
here is a problems solvers installed on a french tubing size , some folks strongly prefer the cage spaced / stands off the tube away from the tube for even on modern bikes , i dont know why , but Ive heard it more than once.
Maybe just pull the trigger on elite or one of the above , you can always switch it later ... I bet once you are riding hydrated the appearance concerns will fall away with the bottle in there
. Costs $12 -$20 bucks to find out ?