Minimum cylinder wall depth for a 318 stroker build

I am building a 318 stroker, and my stock-bore block has just come back from a sonic check with "undesirable" cylinder wall thickness..

Here is what I have (reading from top of bore / middle / bottom) :

Cylinder 1: OUTER SIDE: 270 /208 / 241, INNER: 194 / 148 / 186
Cylinder 2: OUTER: 194 / 174 / 208, INNER: 233 / 194 / 219
Cylinder 3: OUTER: 208 / 186 / 223, INNER: 226 / 194 / 174
Cylinder 4: OUTER: 167 / 148 / 174, INNER: 194 / 167 / 241
Cylinder 5: OUTER: 208 / 215 / 174, INNER: 152 / 130 / 183
Cylinder 6: OUTER: 194 / 183 / 208, INNER: 194 / 174 / 223
Cylinder 7: OUTER: 223 / 194 / 241, INNER: 197 / 156 / 215
Cylinder 8: OUTER: 208 / 156 / 204, INNER: 223 / 183 / 324

The numbers I am most concerned with are Cylinder 1 middle inner (148), cylinder 4 middle outer (148), cylinder 8 middle outer (156), and especially cylinder 5 middle inner (130). With a standard 30 thou overbore that leaves me at 115 thickness.

Given the extra strain of a 4" stroker (worse rod angle, higher piston speed), would this be considered unacceptably thin for a mild street motor ?

In Australia 318's aren't impossible to find - they're relatively common compared to 360's - but they aren't exactly laying around in wrecking yards either (there never were that many sold here, and the ones that are still around aren't cheap by US standards). I don't want to go 360 for a few reasons.

Any and all opinions welcome :-D

Dean.

EDIT: Sorry, title should have read wall THICKNESS but I can't change it :) DUH.