Good quality standard velocity .22's are not going to be cheap. Lower grades of Eley [Club, Target,Sport] are good choices as is Wolf.
RWS 'Target' or SK Jagd 'Rifle Match' will probably outshoot anything domestic except maybe Federal '711'. With the run on .22's these days I can't say if any are available.
Try
www.champchoice.com orwww.creedmoresports.com