If 4 out of the 5 bolt holes are OK, you can get away with super gluing the stripped one in place.
Clean the bolt hole with acetone using cotton balls held with tweezers and be sure to do a thorough job. Also clean the face where the chainring will mount, and the corresponding spot on the ring. Mount the granny using the 4 good bolts and tighten (don't strip these). Now apply some super glue into the bolt hole, insert the last bolt and spinn it to spread the glue and use a C-clamp (have ready in advance) to hold the bolt and chainring tight to the face of the crank. Allow it to cure for a while and enjoy your repair.
It won't last forever, but you'll be able to get use out of a crank you might otherwise throw away, without sinking dough into it.
__________________
FB
Chain-L site
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