Hey Dave i think you mean undersize bearings, almost everone sells them. The oversize bearing comes with an HX.001/HX.002. i think if you get a .001 undersize bearing it will not be too much clearance for a B/BLK stroker, i try to put .0025/.003 min clearance on every B/BLK i build and run 20/50 oil.
JMO
Zip.