To whom? The BSPA and the clubs, or to the potential sponsor?
I would suggest the figures could be very far apart! It would also depend on how much media coverage could be guaranteed from 2014 onwards, unless the sponsoring company had very close links to the sport already and would get 'a return on its investment' in increased product sales,for example.?!
ps. To be thinking about this and posting it at 0455 hours? I think you need some more quality sleeping time!!