SPI under cyclone IV , number of LVDS recieves ?

Chapter 9 of the embedded peripherals ip user guide (https://www.altera.com/literature/ug/ug_embedded_ip.pdf) covers Altera's SPI peripheral. This will work in Cyclone IV. That should allow you to do something a little better than bit-banging.

As for LVDS - have a look through the cyclone iv device datasheet (https://www.altera.com/content/dam/altera-www/global/en_us/pdfs/literature/hb/cyclone-iv/cyiv-53001.pdf). 480Mbps is quite punchy - is that DDR? Look at table 1-36 on page 1-32. This covers the LVDS data rates you can expect to achieve with Cyclone IV.

Cheers,

Alex