With a 7' paraboloid reflector, that would cover about a 7' circle. However the hood alone would cost hundreds of dollars if the best German metal were used. I don't think the 7' are made any more.

The ballast is the major component. The ballast is like the engine, the bulb is like the transmission.

Very few people buy new 1000w MH any more, they have been obsolete for almost 20 years. Ever since the development of super-hps like Hortilux, which has a higher output to compensate for the less blue, and actually works better than a MH even in the veg phase (for most varieties).
Almost 10 years ago, HPS became obsolete (for plants under 2.5' at harvest) with the development of CMH or ceramic metal halide, an efficient full-spectrum light.

hello, thanks for answering.I guess I should have done my homework better.I had hps 400 watt lamp for about six years and I got heavy into succulents with caudexs and read that they do better under mh lamps. thanks joe

The most common CMH bulbs are 400w retros
that work on the 400w HPS ballast. Philips
and GE make them. Expect about 50% more
yield with CMH compared to HPS.