Suggestions for replacing a tree stump covered in ivy

This arrangement has been in our garden for a long time as far as we can tell.
There are 2 stumps, one has honeysuckle, Virginia creeper and a wonderful climbing rose. The other is swamped in mature ivy and as we realised today, rotten and unstable. It was easily rocked around by hand.
We've chopped it back to take away some of the weight but want to replace it with a new tree next year.
It needs to be something around 12ft tall within a couple of years (provides privacy) and not something which will grow too big or have really long roots. I love japanese maples or anything with reddy pink hues in autumn.
All advice appreciated! Will add some pictures in a minute.

 

Japanese Acers are slow growing so you would need to buy a mature one to get to 12ft in height, which would be very expensive.

I would have thought that for anything to reach 12ft in two years, you'd have to buy a large/mature plant so it won't be cheap, but there are cheaper alternatives than an Acer. This place sells mature Acers if you are interested.

I have a Prunus Royal Burgundy which has red/purple leaves all year round and lovely double blossoms in spring. Not bought anything from that site so can't say if they are any good or not.

I'd suggest contacting some specialists in mature trees and asking what they would suggest within your budget.

How tall do you want it to be eventually?
Will there be space for the roots, ie what are you doing with the stump's roots? If there's plenty of space around them that's fine, but if you want to plant it in the same space you'll need to dig all the roots out.

 

I don't really want it to be tall- say 4m max, though I don't mind pruning. I'm wondering that an acer wouldn't be sheltered enough in that spot as well as the cost and slow growth. I did find this which I'm keen on, but there's not much info on eventual height.
http://www.ashridgetrees.co.uk/standard-large-trees/large-trees/acer-freemanii-autumn-blaze
I don't want something that will end up casting a massive shadow over the garden, which is east facing. Sun goes down over the front of the house and tree is at the front to the side if that makes sense. (Corner plot)

Edited to add- we will fully dig out roots of the stump and ivy, there's plenty of space in the area though will prob plant the next tree slightly further away from the hedge behind it.

 

And I like the look of the prunus, being a cherry does it self seed much?