DCF, I-864 and tax transcripts

Question: Do you need to have official IRS tax transcripts, or would a combination of a copy of a 1040 and W2/payslip be sufficient for evidence of income on the I-864?

Background:

I've been a long time lurker and have learned sooooo much from this site. I used all the advice here to get my UK spouse visa, and now I'm in the process of getting a green card for my husband so we can move back to Michigan together.

We are doing DCF and will be sending the Notification of Readiness shortly. We've got all our paperwork in order, except one thing. My dad (our joint sponsor) and I both requested tax transcripts from the IRS over a month ago, but neither of us has received anything back from them. I'm getting antsy because we were hoping to be moving in November so we really need to get that interview scheduled. 

In case it matters at all, I have only had a UK income since 2008 and my dad is retired but his pension is significantly over the poverty line for our household size.

So, my question is whether or not those IRS transcripts are absolutely necessary. There's still a chance they'll come in the next month or so. My dad and I both have copies of our 1040s for the last 3 years, as well as pay slips (me) and pension statements (him). Will that be enough for the I-864?

Thanks in advance!

I didn't use official tax transcripts, I provided copies of the 1040's I filed while living in the UK.

Bear in mind this was 2 years ago, but they didn't ask anything further than what I provided. I was not using income as my basis for being the sponsor, I've no idea if that affects anything.

Good luck.