Code 1A Stamp with valid TIER 4 visa

[Laysz]

Hi everyone, I'm new in the forum and I hope someone can help me. I'm a non EEA national (I'm brazilian) with a TIER 4 visa valid until Jan/2016. This month I got married with an EEA national (he is spanish) here in the UK. He is here since 2012 exercising treaty rights working. We thought about ask the Residence Card for me, but, I need to go to Brazil in September (very important trip, everything were booked a long time ago), and I wanna know if I could get a code 1A stamp in the airport (I will not have time to ask the Family Permit in Brazil), even if my tier 4 visa is still valid, but I already finish my agreement with the university. And, if I get this visa, can I work in the UK? I already have a Insurance Number. I don't wanna ask for a Residence Card because normally takes 3 or 4 months to arrive and in 5 months we will leave the UK and move to Spain (without intend to come back).
I will arrive at Heathrow, from Frankfurt, and my husband will be in the airport, and I will be with the marriage certificate, a copy of his passport, my payslips, his payslips, a letter from his work, our house contract, my bank statement, his bank statement and the bank statement of our joint account. Thank you to everyone.