I think they'd ask for a first rounder, but would ultimately go for a 2xsecond rounder trade. Ie. A future second rounder plus a pick in the low 20s.
If we are keen on going for indigenous talent I'd much prefer we tried to grab the Hill brothers based on the rumours of Brads wife coming back here and them being potentially a package deal. Brad was traded to Freo for pick 23, and I think Stephen would cost a pick in the 30s.