If this is including swim platform or the room required for outboards and the bowsprit, you will be looking for a boat around 26/27 feet. Here is one suggestion - Nordic Tug 26 with an overall length of 28' 9".
Note: To maximize space you will be better of with a stern drive or straight shaft drive boat, not outboards that eat valuable space.
PS: if you are adding a dinghy which most likely will be on davits off the swim platform, that will eat some inches. A dinghy/davit would fit on the back of this Nordic Tug. Look around for other "like" boat designs.
Edited this in: An older Nordic Tug 26: