Oh dear God! 318 stroker

Cylinder wall thickness may be very similar. All LA engines are thin wall castings keeping weight down, but limits the amount the blocks can be overbored. 0.040" to 0.060" is considered maximum on most modern engine blocks of any manufacture. For a performance build with higher cylinder pressures, some are recommended 0.030" maximum.
The A block 315 and 318 CID Polyspherical engines were not thin wall and can be bored out more. By how much I do not know. The Poly engines were heavy thus the lack of the L that LA engines have. So it may be possible to bore an A engine out 0.125" oversize. Chev 283 early blocks could be safely bored that much to fit 327 pistons. They called this a 301 but bore and stroke are identical to the Z28 302 dimensions. Later blocks were thin wall and can not be bored over 0.060".