Does anyone know of a source to start searching for a daily recordkeeper for DC plans?

(not meaning to sound chirpy) Try the yellow pages under P for Pension Administrators. If you don't want to go with a local administrator, someone will direct you to a larger concern. I would venture to guess that at least half of the Third Party administrators these days administer daily valuation plans. If you happen to call a TPA that doesn't, they will direct you to someone in your area that will.

You might want to keep a record or spreadsheet of the various administrative charges, including legal documents, and compare costs according to those items you feel are most important.

If you work with a CPA and/or attornies, they can also refer TPA firms.

In addition, any mutual fund company (Fidelity, etc.) has daily valued products. Check their websites for more info.