How to move all vertical scrollbars to the left side?

I am left-handed and recently started using the touchscreen on my laptop more. There is even a bluetooth connected stylus available for it that works quite well for painting with applications like MyPaint or Gimp.

However, whenever there is a dialog or window that has a scrollbar, it is annoying for a left-handed person to use the vertical scrollbar, which is usually located on the right side of windows.

For instance in MyPaint, the brush selection dialog is quite hard to use with a stylus held in the left hand. Also the layers dialog in gimp and so on.

Is there a way to tell Ubuntu/Gnome that I want all vertical scrollbars to appear on the left side in general (as in "not per application")? Or at least for all GTK-based applications?

As a left-handed person I feel discriminated.

Followup:

It seems that left-handed touchscreen users are a minority out there, probably touchscreen users in general. Maybe I was naive to assume there would be simply some switch to flip. All answers so far are informative and helpful, yet not quite answering the question. I'll let the engine decide about the bounty.

The option mentioned by other answers is deprecated in version 3.10.

GtkSettings:gtk-scrolled-window-placement has been deprecated since version 3.10 and should not be used in newly-written code.

This setting is ignored.

_{Source: Gnome - GtkSettings}

AFAIK, It is difficult to get all apps with scroll to the left. Even if the source of GTK3 libraries is modified to get it, It will affect only apps which uses gtk-scrolled-window. Not apps which compose their own window using scroll component.

There are references on moving the vertical scroll bar to the left in Gnome Terminal and LibreOffice but I haven't found the exact methods yet. If you use Firefox extensively, moving the scroll bar to the left will help enormously:

You need to change your settings in about:config. Here's what to do:

1. Enter about:config into the address bar (if it gives a warning about your warranty, click the button to say you'll be careful)
2. Enter layout.scrollbar.side into the search box at the top of the page
3. Double-click the result and replace the current value with a 3 when the prompt comes up
4. Click OK and then restart Firefox.

Source

So far no luck finding left-handed details for MyPaint or Gimp. However there is a left-handed mouse Q&A that might be helpful: How to set left-handed mouse pointer?

Left hand scrollbar in general

There is a discussion in Stack Exchange User Experience that will interest you. It addresses moving scrollbar to left side not just for RTL (Right To Left) languages (Arabic and Hebrew), nor just for left handed users, but for LTR users that like to hover mouse pointer to left side whilst reading paragraphs. For all these cases a scrollbar on the left side makes sense.

Perhaps between this Q&A and posting an answer on the above link, you can persuade GTK (GIMP & GNOME) developers to resurrect the left side scrollbar.