Yea dealer. It does cost more but it'll last longer. Its too much labour to do it again even if you do it yourself. It is cheaper to buy a JDM engine then all the seals and bearings and time to take it apart clean and put it together.
How do I know? 'Cause I'm rbuilding now. Engine gonna go in this weekend.
I got full engine rebuild kit with all gasket, o-ring and valve seals. It $300+. Then I got rod and crank bearing, 9 sets for around $20ea. Piston ring set for $270. I got a shop to P&P the head, manifold, Tb and clean the block for $1000.
I'm cleaning and painting all other parts. It gonna look nice.