Have you measured the crankshaft jounals for wear? I would have them reground only if they are out of spec. Oversize rings can only be used with oversized pistons. Do you already have the pistons? Once again I would measure the bores and determine if they need to be bored oversize. Main bearings .25 undersize are available from Rusty at
www.*************** they are $101.00. I'm sure he can also source the rod bearings give him a call at (800) 741-5252. Tell him Bill Reimels sent you... Total Seal sells rings for this application. I have used their gapless rings in other applications with great results.