I don't feel right stroking a 340, I'll stroke a 360 till the cows come home but 340's arn't getting any more common. Especially in Canada where people want mega bucks for a 340 core. Plus I want a 340 in my 340 swinger, I'll build a stroker later on a 360 platform if I feel the urge.
My pistons are already for a 3.31 stroke as well, and they will probably protrude above the deck like regular 340 pistons 1.840 compression height IIRC so my only option is to use the edelbrock Performer RPM 340 heads and those can be swapped in at a later date without any changes.