Moss Motors: By now you may know I chat a lot about installing Moss Motors carpet kits, because I've done it three times in the same car over 25 years. The basic bit there is that most of the parts come with a bit of excess material that will need trimming to suit, and there are only a few places with edge binding (as original). The tunnel cover carpet is in three sections. The front section stops several inched forward of the shift lever and is bound on the rear edge only. The center section tucks under the front section and is also bound around the rear edge only. Carpet aft of the shifter has no binding. The only other edge binding is around three sides of the rectangualar cut-out where the floor carpet fits around the raised frame cross rail ahead of teh seat near the frame side rail. Depending on how much padding you use, more oe less, the trimming part may be a good way to make it all fit neatly, but it is extra work. For an information sheet on the details of Moss Motors carpet sets see https://mossmotors.com/media/instructions/454-458.pdf. This is a tech sheet for the MG TD, but same carpet material is used for MGA.

Stock Interiors: StockInteriors.com - Tony Bullum in southern California had this to say:
"I bought my carpet kit from Stockinteriors.com, which came with rear sections of the car AND spare tire cover (no trunk carpet). The price was $179 (April 2011), probably about half of the MOSS price. Amazingly,the pieces required NO TRIMMING, except a little for the "Y" shape at the end of the long frame rail piece. All the pieces had edges sewn in where you would see a "joint" where two meet. I also have no beef with the quality. Overall I am very pleased with the result".