Client has 1099-B for stock sale. The stock was purchased by husband in the 1970's who died in 1982.

Client does not know if the stock was purchased by husband only or by husband & client jointly (Step Up basis?). Can't get original purchase date or price after trying all sources available (Broker (Merrill Lynch... needs acct# to do anything), many online sites, company investment representative, Investment banker who now has the account (says its my problem!), etc)

I do have stock certificate issued to client after husband died... putting stock in name of client and her daughter.

IRS says we need to document stock basis or basis is zero!

Sooo... Can I use the dates on the stock certificates and get the stock price on that date as the basis? This would ignore the original purchase by clients husband nearly 20 years earlier but I have documents to back it up.

Is there a better way to do this whole thing?