Here was my experience from OCS this past summer:
bring the $300 to buy all the small/large bag crap. It cost my company $205 a head, but may be more depending on the season.
Cammies/boots/sea bags are issued by cash sales, but despite the name we did not pay for them right there. The cost of our uniforms and boots was taken out of our paycheck (so we were told).
All cammies were the new MARPAT style, plus tan boots. Don't worry about bringing your own cammies to OCS, you'll just be wasting your money.
As for boots, we were issued 1 pair infantry combat boots, 1 pair jungle boots, both tan. the ICBs are thicker and comfier, but heavier. The jungles, once broken in, are lighter and the way to go on PT, humps, etc., unless you bring your own boots.
In my opinion, 2 pairs of boots is not enough to make it through OCS. I brought a pair of magnum zip-side black boots that i had purchased and broken in months before OCS, these saved my life on humps and PT events (O-course, stamina course, SULE, etc). They were much lighter, more comfortable, and easier to get on and off during those 5 min hump breaks to change my socks. They also allowed me to have one pair of boots to trash on the messy events, one pair to wear around to class, drill, chow, etc, and one just for inspections. the black boots were only allowed during these events, but it seems like you're always doing something messy at OCS.
Nobody knows for sure what the brass at OCS will say about black boots for future classes, but if it is true about the deadline being extended to OCT2004 then I would say go get the best black boots you can find, and break em in. You'll thank yourself at OCS when you're draining dime-sized instead of quarter-sized blisters after taps.