This head is a collector's item. I can't recall how many were made so please feel free to check the specs on that. It's in great condition and please do not forget this is an all tube head.
Get Marshall JCM2000 tone in a smaller size, but don't think this isn't loud. It's not 100 watts loud, but it's loud enough to upset the neighbors.
Please do a search for this head if you have questions.
Here are a few links to the other 50th anniversary models that I found for reference.