I'm not sure that you will be able to get that much sp from minnowbooster tbh. Also it could be unprofitable.
You should try to find a whale and get a better, more sustainable deal (try getting a hold of @yabapmatt and asking him where he got the shit ton of SP for his bot)
As for asking for delegations you could just figure out how much you can afford to give back to the delegators, make a post about it and present them a nice ROI, boost it and see the SP rushing in :)