Several months ago I purchased a Gem roller organ on eBay auction.
After examining the thing and trying to play a couple of the rollers
that came with it, I have determined that it needs some work.  My
question is where to start!

The main problem is that it doesn't develop enough suction.  The
reservoir covering appears to be in good shape with no obvious tears
or holes.  The flap valves on the bottom seem to be somewhat stiff and
don't really seal.  I have no idea what condition the bellows covering
is in.

What should be my first course of action?  Should I just bite the bullet
and recover the bellows and reservoir and replace the flap valves?
Would it make more sense to start at it piecemeal and just replace the
flap valves and see if that helps?  Is there a way to determine the
condition of the bellows covering short of taking everything apart?

Please excuse my ignorance.  As you can tell, this sort of thing is all
new to me.  Any and all suggestions are welcome.

Sincerely,
Matthew Walworth
Littleton, CO