Can I find my employers ein nu.ber through my 2013 tax return? And do y'all have a copy of it?

TurboTax only retains the current and past 7 tax years, the same retention period as the IRS.

The IRS provides tax transcripts for the past 10 years but the transcript will not include an EIN from your business - https://www.irs.gov/individuals/get-transcript

Go to this IRS website if you have lost or misplaced your EIN - https://www.irs.gov/businesses/small-businesses-self-employed/lost-or-misplaced-your-ein

You probably can't get a copy of 2013 and the employer's EIN would not be on it anyway.  And Turbo Tax does not have a copy of your W2.  You needed to keep your own copy.  

Best way to get that EIN is to ask the employer ... they may have changed it since 2013.