Go to Epson Download Page (download.ebz.epson.net/dsc/search/01/search/sea...) and download this files (just search for “V33″:

iscan-data_1.28.0-2_all.deb
iscan_2.29.3-1~usb0.1.ltdl7_amd64.deb
esci-interpreter-perfection-v330_0.2.0-1_amd64.deb

(Version numbers may have changed !)
Installation

Now install first xsltproc:

apt-get install xsltproc

and install the downloaded iscan packages:

dpkg -i iscan-data_1.28.0-2_all.deb
dpkg -i iscan_2.29.3-1~usb0.1.ltdl7_amd64.deb
dpkg -i esci-interpreter-perfection-v330_0.2.0-1_amd64.deb