Hi all,

Apologies, I don't have a high enough post count to post links or photos.

I recently had to replace the forks on my Haibike Sduro Trekking 5.0 after the fork ends sheard off after over/under tightening a wheel.

e-bikeshop.co.uk/Haibike-sDuro-Trekking-5.0-2017

I couldn't find an exact like for like replacement - "SR Suntour NCX 63mm" but I bought something which has similar specs - "SR Suntour SF9 NCX D-LO" - bikester.co.uk/bike-parts/suspension-forks/28-touring-forks/266085.html

I've just come to swap them out and realised the headtube and fork stem on the original are tapered, whereas the replacement I've got has the same diameter stem throughout.
imgur.com/a/ONRBzrz

Is there some kind of adapter I can get for this?

It depends on the headset, but "conversion" fork crowns are available for certain headsets. It may even be economical at this point to replace the headset lower so that you can use one:

https://www.universalcycles.com/shop...2&category=100

Do you know exactly what headset you have?