I'm sorry, an over sight on my end about you not wanting to sync to Google. Export as vcf should work without any problems. I would suggest saving two contact export files (backup to the cloud or pc) and make a nandroid backup in recovery of your current ROM.
With the contacts app opened, press menu. You should be given an option to import/export, and will have options as to where you want the exported file saved.
Let us know how it works out or if you have further questions!
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