You can certainly print that type of pano on a 3800 - I've done many at that sort of size using UDPS or QTR. There have been lots of discussions on how best to load the canvas, but I have always taped a paper leader to the canvas and fed from the normal top feed.
If you want a canvas that gives a Dmax and color gamut similar to a luster paper you might want to try the Innova Phot Canvas Ultra Gloss. It's quite different from any other canvas I've tried in that it gives a Dmax of around 1.8, against typically 1.5 for the average canvas after coating. I've only had samples so far but the next time I need canvas this is the one I'll go for.
Keith Cooper did a review of it - see http://www.northlight-images.co.uk/reviews/paper/innova_canvas.html