IMO A 3/4 ton diesel would not be a good option for you. Just about any 3/4t gas truck built in the last 10 years would be more than adequate for your needs. The $10k premium that a diesel costs (not to mention oil changes and repairs) would be hard for me to justify with as small of a load as you are pulling (relatively speaking with regards to the diesels capabilities) and how few miles a year you will be towing.
Will a half ton pull it?? Sure will. Will it be a relaxing drive? Probably not. Not sure about some of you guys but the last thing I want to do when going camping is be stressed out about having my trailer push my truck around.