I don't think anyone can give a reliable answer based on the information you provided. That's because the answer depends on whether you already have a genome/proteome available. Depends on your final research goals. Depends on the coding density.
But let's say that a coding density is 10% (80 Mb) and you expect half a total coding sequence to be transcribed at any given time (40 Mb). If you want 100x coverage and your reads are 150 bp long, you would need: