The "standard" mirror arms (non-telescoping, non-straight arm) for 47-55 were:

47-50 driver's side (left side) stock/standard equipment mirror arm (for doors with no vent window)
51-55 driver's side (left side) stock standard equipment mirror arm (for doors with vent window)
47-55 passenger side (right side) optional/accessory mirror arm

I do not think that a chrome arm was GM-available from 47-55 (but, use them, if you like them).

I think that there are also no chrome/stainless round mirrors from GM in 47-55.

I use reproduction round black mirrors that are stainless steel under the paint.
I also like convex mirrors on both sides.
And, I like a 6" round mirror rather than the original 5" round mirror.

Do whatever suits your truck/tastes.

Tim
1954Advance-Design.com
1954 3106 Carryall Suburban
1954 3104 5-window pickup w/Hydra-Matic
The 216 and early 235 engines are not "splash oilers" -- this is a splash oiler.