The late summer milkyway has lots of interesting ojects that may be all the more interesting in an 8" vs. 6", so maybe waiting a few months wouldn't be so bad?
As for a case, why? Would you plan on moving it around or traveling with the telescope? Personally, I would save the cost of the case to pay for shipping of the larger scope or buy some nice accessories.
Go here to look for local dealers of Celestrons:
http://www.celestron.com/c2/dealers.php or here for Meades:
http://www.meade.com/dealerlocator/ but I can't find a resource for Orion.
-Veeger