I'm wondering why you want a woodburner converted to gas, instead of just going with gas in the first place...

I've never come accross a wood or gas burner that allowed you to put stones over *every bit* of the metal so that it doesn't show at all.

And while I've seen full massonry wood burners converted to gas without glass doors, I haven't seen an insert of any type without doors. That means you'll have some metal framing-- sorry.

The louver-less or 'clean face' gas models I've seen aren't double sided. My personal problem with these is that you can see the glass. Seems to be an open fire at first glance, and when you realize it isn't, it's quite a let down. Most of these only show a thin metal frame that serves to hold the glass and seperate the facing [stone in your case] from the firebox lining. Here's a good looking model from Fireplaces xtrordinaire:

I think this lennox [magna fire model] is about as clean a face as you'll find for a see through wood burner. I'd talk to the dealer about whether it can accomodate a gas log set, though:

Best of luck on your search!

Might be about as close as you'll come, would be worth seeing in person. You can face it in any material you like, of course.

Info link:

Best thing is to visit local shops where you can compare differnt units side by side.

I personally think you'd be better off with a gas model, where the whole thing has been specifically designed to work together, that has had every piece engineered to work with the rest. Safer than using mis-matched components and having to guess whether the btus of the burner are appropriate for the enclosure, whether there will be enough 'draw' to keep the flame lit, and enough combustion air to prevent back drafting: Let the experts worry about such issues, sez I!