A 300W 120V general service lamp is a little over 6000 lumens. If you get 130V or extended service lamps you give up some light output for the longer life. Initial cost is very low but they don't last very long (750hrs for general service)
I have also installed some 105W CFL's (P/N- eiko sp105/41/med) in many buildings for still somewhat cheap lighting. It produces about 7000 lumens and they have a whiter light. They also have a decent lifespan (rated 10,000 hrs), but they are more expensive to purchase.
High wattage lamps get expensive fast. You're better off buying some lamp splitters or putting in proper fixtures.
300w lamps are like $3-5 a piece, thats pretty cheap in my book.
High wattage incandescent makes sense for applications with low annual hours or cold temps/ect.
If you plan on using them for multiple hours every day then there are better options out there.