Thanks for the links WC. Looks like HTG is down at the moment but I am curious what they are asking for a 150 HPS so Ill hafta keep an eye on it. I couldn't find any reflector CFLs in blue 6500k and they are a pita to find anywhere to be honest. LOWES does carry them but they are $7 a piece. At least they are good lights, reliable and bright.
15 watt R30 6500K fluoros:
http://www.lowes.com/lowes/lkn?action=productDetail&productId=296879-371-60063&lpage=none
A cheaper alternative would be the plain twisty 10watt 6500k GE CFLs from walmart. I think you can get a 2 pack for $5. Can make your own reflectors out of beer cans and mount them horizontally. The 10 watters are surprisingly bright, 490 lumens.
The UVB tubes come in 15" and 18" length, which would fit nice in a 2X2 box. Im not sure if it would be easy to find 15" fixtures though. You can make your own if you have to with parts from LOWES (example in the garbage can pic posted earlier). The reptisun tubes are similar to human tanning bulbs and emulate the sun's UVB very well.
15" Reptisun 2.0 tube $16 shipped
http://cgi.ebay.com/ReptiSun-2-0-Re...0?hash=item2e935a8e74&_trksid=p3286.m20.l1116
18" Reptisun 2.0 tube $20 shipped
http://cgi.ebay.com/Zoo-Med-Reptisu...0?hash=item29fe1931cb&_trksid=p3286.m20.l1116
15" Reptisun 5.0 tube $27 shipped
http://cgi.ebay.com/Zoo-Med-Reptisu...0?hash=item29f9b9c42d&_trksid=p3286.m20.l1116
You might be able to find them in a local aquarium shop or pet stores, but I suspect it would be tough to beat $16.
The UVB fluoros also come in compact CFL sizes but Id have to warn you against using those. They use a different phosphor which emits non solar wavelengths and are technically emitting a hazardous amount of radiation so Id stay away from them (will directly damage the DNA in your skin cells and likely stunt the growth of plants).
You can grow without UVB just fine if you need to cut costs, but if you can get one in there it will increase trichs and potency.
If you run this light combo it will be plenty to grow anything you can stuff into that 2X2 and grow it well. You can get the 70w HPS within 8 inches of the canopy for maximum intensity without damaging the plant tissue, especially once the temps start cooling off next month.