People just don't know how to ship or pack tube amps. They are heavy, especially the Sunn stuff.
You can probably get it working before replacing the caps. Just hook the transformers and leads back up to where they are supposed to go. Also, if the tube sockets were damaged, you should replace them as they will most likely start arcing if they are chipped or cracked in any way. I think they are riveted in too, so you would have to drill out the rivets, replace the sockets with new ones, and then re-rivet them in again. Of course that would involve unsoldering and resoldering all the connections to the sockets too. Make sure to draw up a layout of how it is now before you do that.
The best solid state rectifier to use would be the WZ34 Copper Cap from webervst. It will plug right into the socket and is only $20. I'm using one in my 200S because I upped the filter cap values in the first 2 stages for more bass and the tube GZ34 can't take the higher cap values. I went to 110uf and 100uf instead of the stock 30uf and 20uf or whatever it is in the first two stages. Made a VERY big difference in the bass response and the amp sounds a LOT better now for bass. If you do this, you'll have to use series connected, lower voltage caps and 220k 1w resistors in parallel to each cap. For the 110uf, use two 220uf 350v caps. It would also be beneficial to rearrange the choke and drill some holes to add some turret lugs or connectors of some sort. This way you get more room in the chassis to use all the series connected caps, and you can still keep the layout well arranged. I could send pics of what I did if you want? I also added a ground buss and some other stuff, but you could get the idea. You could also just get the exact replacement can cap from vibroworld and triode electronics and other places, but that isn't as good of a solution in a number of ways, probably costs more, and you don't have as good of bass response. If you were in the Portland, Oregon area, I could help you out.