A few stainless Nakiri's here within your budget. Remember to include UK customs charges. Will be 20% VAT plus £12 handling charge from Royal Mail....
https://www.sakaiknife.com/search.asp?bunrui1=202&bunrui2=6&bunrui3=2&junflg=0&dsptype=0
I bought a carbon one from this site a month or so...