Motherboard wise there are some Asrock options within the same price range, but some have concerns of running them with X3D chips due to failures. If you do go for an Asrock board be sure to update to the latest bios and keep an eye on future bios updates.
PSU I can't see anything within the same price range, the two closest which are in stock otherwise would be the following:
My basket at OcUK:
Total: £284.98 (includes delivery: £0.00)
Obviously you're paying a bit more but OCUK's in stock PSU/Motherboard selection is a tad dire right now.
I'd be inclined to shop around a little.
Edit: Whoops, wrote this out half an hour ago and forgot to hit enter, micky beat me to it!