Your best contact is Tweed- his web site is at http://tweedsblues.net/ and is also a 'Catter and can be pm'd on this site. Tweed changed the cone for one of the Monolator cones, and has given good reviews.
I have had one of the "far eastern" resonators for over a year now and (touch wood) have had no problems at all. I have changed the bridge for a home made hickory one to suit the action I wanted - my own choice, as I was told maple or cherry was the better alternative, but I tried a few and Hickory works for me.
I am a finger picker and couldn't use a slide if my life depended on it.
Changing the cone I would guess is quite easy, I take mine out to clean about every couple of months as the dust does build up. I also use car polish on the metal body one a month and window cleaner to wipe off the fingerprints.