I had broken cheap oscillating tool.
It cost 9euros 4 years ago, it lasted 2 weeks then motor burned.
Found it some time ago, and got this idea.
I think this actually could be nice add for the dremel attachments collection.
Those have enough power for this, and this would make it real multitool.
Whole idea can be seen from this picture:
Two collets/chunks/adapters or what those are called... Anyway, those are used to attach flex shaft attachment to rotary tool. Nail works as an axle.
Cut the motor with angle grinder.
Then "turned" axle with angle grinder, did threads for the collet.
Used Dremel cutting guide attachment as an casing, secured it with epoxy and screws.