1.You can activate as many info structures you want, but do keep in mind that each info structure you activate (Filled with archived data) will occupy space in the r3 data base, so i recommend you to activate only SAP_SD_VBAK_001 which supports all the scenarios.
2. No need to retrieve data back to sap, just activate the info structure and fill it.
goto--->Tcode (sari)--->status---->status per info structures--->select the info structure---->fill structures--->execute in back ground.
after filling the info structures you should able to see the archived data in VA03 and ALo1.
With regards,
Tony.