The QF/AY joint fare is QF to Asia/AY to HEL and back

Can get 1 leg Asia-Europe on QF for a modest surcharge (under $1K) but other leg must be on AY Europe-Asia or vv. Still a good fare on QF. Otherwise sometimes BA J fares are available on QF codeshares (and often half the QF price), but I suspect those require BA code on all sectors which you might not be able to do ex-PER.