The licence can be obtained in Mora.It is difficult to explain where the place is but there is a tackle shop right next to the bridge and they will tell you and draw a rough map.It's only a few hundred yards away.Cost wise,they are(or were)15 euros.If you have a bus pass they will last for 5 years if not they are for one year.As for the motorhome,well that could be interesting.I think you'd be wise parking up somewhere and walking to check the access first.I have seen large caravans camped by the river.