We were hoping to replace the entire lot but having had quotes of a few grand it won't be getting done for a while. So I thought in the meantime I'd just paint the spindles white and add an oak banister like in the picture attached. Is this an easy DIY job - by banister is only 1 small run.
Only needs a light sand and then use Zinsser BIN 123 primer. It does say you don't have to sand to use it (it is used to prime laminated furniture before undercoat and painting)
Fitting a banister is not straight forward. You have to fit each spindle in and the spacer between each one. Plus attach it to the post. Unless you are very good at DIY then I wouldn't tackle it. I wouldn't and Dh and I plumb in bathrooms/tile/lay flooring etc.
Personally I would go down the strip the banister route, just the banister and paint the spindles. If you haven't ever painted spindles before have a dry run with either a roller or brush depending what you are using to see how you will approach it.
I have stripped/sanded/painted a few staircases and these days I pay a decorator to do it because it pisses me right off to do all the fiddly bits. Cost me less than £100