One way to bind data to specific blender spaces.

SpaceContext.py

# snippet to add data to specific space-views by dertom
#
# - alter SpaceContext-PropertyGroup to fit your needs
# - import the SpaceContext to your script: import SpaceContext
# - when needed get the space-context (your SpaceContext-PropertyGroup) via:
#   currentSpaceContext = SpaceContext.retrieveSpaceContext(context)
# 
# For now you have to press a button to trigger the operation that creates the context for a single space
#
# This sample is indended to be run from the text-editor and will create a panel in each view_3d spaces ui-region. 
# For testing open multiple view3d-spaces, add the space-context via button and then you can choose one object which
# will be set in the new space-context (independ from the view data)

import bpy


# The spacecontext: define per space data you want to keep in each space-view:
class SpaceContext(bpy.types.PropertyGroup):
    objectName = bpy.props.StringProperty() 


# create a data-slot for the current space. not sure how to call this automatically from
# panel's draw-method. For now you will have to press the button once to init spacecontext
class SpaceContextOp(bpy.types.Operator):
    
    """Tooltip"""
    bl_idname = "utils.spacecontext"
    bl_label = "Create SpaceContext"

    @classmethod
    def poll(cls, context):
        return True

    def execute(self, context):
        spaceSignature = getCurrentSpaceSignature(context)
        # check if there is already data for this space
        world = bpy.data.worlds[0] 
        pos = world.spaceMapping.find(spaceSignature)
        data = None
        if pos==-1: # no slot for this space-view? create one
            data = world.spaceMapping.add()
            data.name = spaceSignature
    
        return {'FINISHED'} 


# get the spacecontext-signature,a unique-string,for the given context
def getCurrentSpaceSignature(context):
    current_space = context.space_data
    
    for screenIdx in range(0,len(bpy.data.screens)):
        screen = bpy.data.screens[screenIdx]
        
        for areaIdx in range(0,len(screen.areas)):
            area = screen.areas[areaIdx]
            
            for spaceIdx in range(0,len(area.spaces)):
                space = area.spaces[spaceIdx]
                if (space == current_space):
                    name = str(screenIdx)+str(areaIdx)+str(spaceIdx) 
                    return name

# This is the call you want to do to receive the current space-context
# get the spacecontext or None
def getCurrentSpaceContext(context):
    signature = getCurrentSpaceSignature(context)
    world = bpy.data.worlds[0] 
    pos = world.spaceMapping.find(signature)
    if pos == -1:
#        print("NO CONTEXT FOUND FOR SIG:"+signature)
        return None
    else:
 #       print("FOUND CONTEXT FOR SIG:"+signature)
        return world.spaceMapping[pos]


class SpaceContextPanel(bpy.types.Panel):
    """Testing Space-dependent data"""
    bl_label = "SpaceContext Demo"
    bl_idname = "spacecontext_demo"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'

    def draw(self, context):
        layout = self.layout
        
        spaceCtx = getCurrentSpaceContext(context)
        
        if not spaceCtx: # no spacecontext bound to this space? show button to create one
            layout.operator("utils.spacecontext")
        else: # spaceCtx found
            layout.prop_search(spaceCtx,"objectName",bpy.data,"objects")



def register():                        
    bpy.utils.register_class(SpaceContext)
    bpy.types.World.spaceMapping = bpy.props.CollectionProperty(type=bpy.types.SpaceContext)
    bpy.utils.register_class(SpaceContextOp)
    bpy.utils.register_class(SpaceContextPanel)
        
def unregister():
    bpy.utils.unregister_class(bpy.types.SpaceContextOp)
    bpy.utils.unregister_class(bpy.types.SpaceContext)
    bpy.utils.unregister_class(bpy.types.SpaceContextPanel)
if __name__ == "__main__":
    register()