Ok. Sounds like this is squashed already.
On to the pics. Let's see em! I have a 521 myself and enjoy seeng what other peoples tastes are. Oh and welcome aboard.
I havent had a chance to check usps , ups , or fedex but i got some dimensions for you during lunch. So you can get an idea.
Package weighs 18 lbs.
Dimensions: 27"x7"x25"
I think I still have a brand new one , still in the box(unopened). Fits the 620 and I'm looking to get $100 for it. I paid around $170 for it. I'll get pics later this evening.