FWIW.. 0.027" from Cometic is the thinnest head gasket I know of. Cometics ought to have the heads re-surface to a certain finish to hold well. There also is the .028" thick Mr Gasket 1121G.
Oops, the Mr Gasket .028” , so it looks like 8.53:1, (not great but at least not lower.) From what I’ve seen the Mr. Gasket head gaskets work well for people. (And in this case adds a calculated .210 to the compression.)
