Wolf Tooth Oval chainrings for Shimano GRX cranks - these are the 11 Speed versions.

https://www.wolftoothcomponents.com/collections/chainrings/products/oval-110-bcd-asymmetric-4-bolt-for-shimano-grx-cranks

38t - quite new (probably less than 300 miles) - £40 posted 

42t - more miles (probably about 1,000 or so) but found these last a really long time. £35 posted  

Payment through PayPal (if you cover fees) or bank transfer. Drop me a line via (flakey) PM or at richard ‘dot’ bowman ‘at’ outlook ‘dot’ com