As you mention Ktech can supply bushes and OEM seals as they did my pair not so long ago.
Jan De Vos on Facebook (Redfox Grinta) is selling "new" tubes.
For rechroming the fork tubes there are many to choose from or you can contact Nick at Allbike Engieering and he will make you some if he hasn't got them already.
Personally I re anodised my tubes (write up in my SP4 rebuild) at Daventry Metal Finishers but to be honest they are not perfect. Once corrosion gets into them (high zinc content) you cant really get it out without cutting deep intothe material and anodising doesn't grow from corroded aluminium.
Picture attached is of my re anodised outer tubes by Daventry Metal Finishing and rebuilt forks/rear shock by Ktech. Fork tubes were fine and I chose not to re anodise the fork bottoms or knurled nut.
